The prices may depend on to whom they were available. I recall reading some contracts in Williams' The Knight and the Blast Furnace in which 14-15th c. English kings were ordering quantities of armour and weapons in the five-digit range. Presumably this wasn't the best stuff, but they likely were getting a bulk discount.
The prices vatied a lot. A suit of ready made Milanese arnor might cost 8 pounds (see price list), while the armor for a prince was 340 pounds. So price depended on the quality.