The entire harness must be from a single period within that range. Equipment fully covered by Surcoats, Jupons, and Coat-Armor need only meet Society safety standards, provided that the covering garment is appropriate to the rest of the harness, and authentic in appearance, and the dubious harness is entirely covered and does not impart an inauthentic outline to the covering garment.
More authentic equipment is encouraged.
They need not be closed greaves. Sabatons are splendid, medieval shoes are acceptable. Sneakers that are all black or brown are acceptable, Hose is good. Sweatpants and, if visible, socks of a matching color, are acceptable. There are hardly any cases where armor covers enough of jeans to make them acceptable.