Question: The DUX-53 and DUX-59 were submachine guns designed at the Oviedo Arsenal in which country, a large number of these weapons were produced for the West German Border Guard, and was later licensed to be produced by Anschütz and Mauser, a German arms manufacturer?

Context paragraphs:
Sa vz. 23: The CZ Model 25 (properly, Sa 25 or Sa vz.  48b/samopal vz.  48b – "samopal vzor 48 výsadkový", "submachine gun model year 1948 para") was perhaps the best known of a series of Czechoslovak designed submachine guns introduced in 1948.  There were four generally very similar submachine guns in this series: the Sa 23, Sa 24, Sa 25, and Sa 26.  The primary designer was Jaroslav Holeček (1923–1977), chief engineer of the Česká zbrojovka Strakonice arms factory.

Small arms: In international arms control, small arms include revolvers and pistols, rifles and carbines, assault rifles, submachine guns, and light machine guns. Together with light weapons (heavy machine guns; hand-held grenade launchers; portable anti-aircraft and anti-tank guns; recoilless rifles; portable launchers of anti-aircraft and anti-tank missile systems; and mortars of calibres of less than 100 mm), they comprise the Small Arms and Light Weapons (SALW) protocol.

DUX submachine gun: The DUX-53 and DUX-59 were submachine guns designed at the Oviedo Arsenal in Spain.  They were based directly on the design of the Finnish 9mm Model 44 submachine gun, which in turn was based on the Soviet PPS-43.  A large number of these weapons were produced for the West German Border Guard, and was later licensed to be produced by Anschütz and Mauser until the mid-1950s.

Arsenal submachine gun: The Arsenal M23 submachine gun (Estonian: "Arsenali püstolkuulipilduja" ) (also known as Arsenal Tallinn) was an Estonian submachine gun from 1926 through 1935.  These submachine guns were designed and produced in the Estonian military equipment factory "Arsenal" in Karjamaa, Tallinn, but production was not more than 600 units.  The weapon was chambered for the 9x20 mm semi-rimmed Browning cartridge to be compatible with ammunition for the Browning FN M1903 pistol which had been adopted by the Estonian Army.  It operated on the blowback system and was essentially similar to the MP18.1; having a wooden stock, slotted barrel jacket, and horizontal left side magazine feed.  A uniquely slender 40 round single column box magazine led to frequent cartridge feeding problems; and cooling fins which were machined lengthwise along the barrel to promote cooling air flow when firing (similar to the Lewis machine gun), unnecessarily complicated production.  It was used by the combat support units of the Border Guard, the Estonian Defence League and the Estonian Defence Forces.  The Arsenal submachine gun was replaced in Estonian service by the Finnish Suomi KP/-31 submachine gun in 1938.  The Estonian Army sold a few samples to Latvia and all of the remainder found their way to Republican forces during the Civil War in Spain.

Luger pistol: The Pistole Parabellum 1908—or Parabellum-Pistole (Pistol Parabellum)—is a toggle-locked recoil-operated semi-automatic pistol.  The design was patented by Georg J. Luger in 1898 and produced by German arms manufacturer "Deutsche Waffen- und Munitionsfabriken" (DWM) starting in 1900 with other manufacturers such as W+F Bern, Krieghoff, Simson, Mauser, and Vickers; it was an evolution of the 1893 Hugo Borchardt–designed C-93.  The first Parabellum pistol was adopted by the Swiss army in May 1900.  In German Army service, it was succeeded and partly replaced by the Walther P38 in caliber 9×19mm Parabellum.

Mauser: Mauser, begun as Königliche Waffen Schmieden, is a German arms manufacturer.  Their line of bolt-action rifles and semi-automatic pistols have been produced since the 1870s for the German armed forces.  In the late 19th and early 20th centuries, Mauser designs were also exported and licensed to a large number of countries which adopted them as military and civilian sporting firearms.  The Mauser Model 98 in particular was widely adopted and copied, and is the foundation of many of today's sporting bolt action rifles.

Rudi Arnstadt: Rudi Arnstadt (3 September 1926 – 14 August 1962) was an East German border guard who was shot and killed while serving as a captain of the border troops of the former East Germany.  He was shot by Hans Plüschke, a 23-year-old West German border guard.  According to West German officials, Plüschke was returning fire after his patrol was shot at.  The incident took place at Wiesenfeld on the East-West border in the East German province of Thuringia.

Bofors 57 mm gun: The Bofors 57 mm guns are a series of dual-purpose naval guns designed and produced by the Swedish arms manufacturer AB Bofors (since March 2005 part of BAE Systems AB), designed in 1964 as a revision of the 57 mm lvakan M/50 used on the Halland class destroyers. Production of the baseline 57 mm Mark 1 variant began in 1966 and was initially used to equip smaller coastal patrol craft and fast attack craft .  The gun is remotely controlled, usually by a fire-control computer but, as a redundancy measure, the crew can also train and aim the gun using instrument panels that are either on or in direct contact with the gun.

Mauser C96: The Mauser C96 ("Construktion 96") is a semi-automatic pistol that was originally produced by German arms manufacturer Mauser from 1896 to 1937.  Unlicensed copies of the gun were also manufactured in Spain and China in the first half of the 20th century.

MCEM 2 submachine gun: MCEM-2 (Machine Carbine Experimental Model 2) submachine gun was produced only in prototype form, but was one of the very first submachine guns to combine wrap-around bolt and magazine in pistol grip, features later copied in the Czechoslovak Sa vz.  23, Israeli Uzi and a great number of other submachine guns.  MCEM-2 was the second prototype in a line of experimental submachine guns, designed in Britain in 1944.  It was envisioned as a possible replacement for the STEN submachine gun then in service.  The MCEM-2 was developed by Jerzy Podsedkowski, a Polish constructor involved in work on Vis and Mors, who fled from occupied Poland to Britain.  It is believed that prototypes of MCEM-2 were made before the end of WW2, and its derivatives MCEM-4 and MCEM-6 were tested soon after the war.  The latter modifications differed mostly in adoption of the rate-reducing mechanism, incorporated into trigger unit; the rate of fire therefore was decreased from 1000 to more realistic 600 rounds per minute.  Nevertheless, neither prototype was found suitable for adoption, and several years later British army adopted a more conventional submachine gun, the Sterling-Patchett.

Supporting paragraphs: DUX submachine gun Mauser
Answer: Spain