Question: Where is the company which introduced the Thompson/Center Contender based?

Context paragraphs:
Thompson/Center Ugalde: The Thompson/Center Ugalde, or TCU family of wildcat cartridges, was developed by Wes Ugalde of Fallon, Nevada, by necking up .223 Remington brass to accept larger bullets.  The cartridges were developed for the Thompson Center Arms Contender single shot pistol, and are widely used in handgun metallic silhouette competition and handgun hunting.

The Contender (season 2): The Contender 2 is a reality television show based on the sport of boxing, but with an element of the (welterweight) competitor's lives and relationships with each other within the show's living quarters, based in Pasadena, California.  Filmed in January and February 2006, the show began airing on July 18, 2006.  The winner of "The Contender Season 2" was decided in a bout at the Staples Center, Los Angeles, broadcast live on September 26, 2006, winning a purse of US$500,000.  The Contender 2 was shown on ESPN in the USA, in the UK on ITV4, in Canada on TSN, in Australia on FOX8, on TV2 in New Zealand and on AXN in Asia.

Brennabor Typ Z: The Brennabor Typ Z, launched in 1928, was a car introduced by the Brennabor company, replacing the Brennabor Typ R, as the company’s contender in the medium-sized car sector, had been a best seller on the German market during the modest return to economic growth that characterized the middle years of the decade after the reparations issue had, to an extent, been resolved.  The Typ Z was itself replaced after just a year by Brennabor Ideal Typ N which would represent a more comprehensive upgrade

Thompson/Center Contender: The Thompson/Center Contender is a break-action single-shot pistol or rifle that was introduced in 1967 by Thompson/Center Arms.  It can be chambered in calibers from .22 Long Rifle to .45-70 Government.

.357 Remington Maximum: The .357 Maximum, formally known as the .357 Remington Maximum or the .357 Max, is a super magnum handgun cartridge originally developed by Elgin Gates as the wildcat .357 SuperMag.  The .357 Maximum was introduced into commercial production as a joint-venture by Remington Arms Company and Ruger in 1983 as a new chambering for the Ruger Blackhawk.  Shortly thereafter, Dan Wesson Firearms and Thompson/Center Arms introduced firearms in this cartridge.  United Sporting Arms chambered it in their Silhouette series single-action revolvers.  It is a .357 Magnum case lengthened 0.300 in .  Based on the .357 Magnum cartridge, a revolver or single-shot pistol designed for the .357 Max can fire .357 Magnum, .38 Special, .38 Long Colt, and .38 Short Colt rounds.  Intended primarily as a silhouette cartridge, such high velocity and energy levels have hunting applications.  SAAMI pressure level for this cartridge is set at 48000 psi CUP.

7-30 Waters: The 7-30 Waters cartridge was originally a wildcat cartridge developed by author Ken Waters in 1976 to give better performance to lever-action rifle shooters than the parent .30-30 Winchester cartridge, by providing a higher velocity and flatter trajectory with a smaller, lighter bullet.  By 1984, Winchester introduced a Model 94 rifle chambered for the 7-30 Waters, establishing it as a commercial cartridge.  In 1986, Thompson/Center began chambering 10-inch, 14-inch, and 20-inch Contender barrels for the cartridge.

Thompson Media Group: Thompson Media Group, LLC, originally established as Thompson Publishing Group, Inc. was founded in 1972 by Richard E. Thompson.  Thompson Media Group is an American privately held media company that specializes in providing compliance, regulatory, and market information through its four operating units: Thompson Information Services, The Performance Institute & American Strategic Management Institute, AHC & BioWorld, and Sheshunoff Information Services, A.S. Pratt, & Alex Information (collectively, SIS).  Thompson Media Group, LLC, is based in Washington, DC.  Thompson Media Group LLC established their name during reorganization in 2011.

Old Thompson: Old Thompson is a brand of blended American whiskey produced by Barton Brands, which is now owned by the Sazerac Company.  It is known for its low price among brands of American whiskey.  The company refers to it as "an excellent value".  The brand dates back to 1904, when it was introduced by the Glenmore Distillery Company which at the time was owned by the brothers James Thompson and Francis P. Thompson.

Thompson/Center Arms: Thompson/Center Arms is an American firearms company based in Springfield, Massachusetts.  The company is best known for its line of interchangeable-barrel, single-shot pistols and rifles.  Thompson/Center also manufactures muzzle-loading rifles and is credited with creating the resurgence of their use in the 1970s.

5mm Remington Rimfire Magnum: The 5mm Remington Rimfire Magnum or 5mm RRM is a bottlenecked rimfire cartridge introduced by Remington Arms Company in 1969.  Remington chambered it in a pair of bolt-action rifles, the Model 591 and Model 592, but the round never became very popular, and the rifles were discontinued in 1974.  About 52,000 rifles and 30,000 barrels for the T/C Contender pistol were sold during its brief production run.  Remington discontinued the cartridge itself in 1982, leaving owners with no source of ammunition.

Supporting paragraphs: Thompson/Center Contender Thompson/Center Arms
Answer: Springfield, Massachusetts