If you are quoting me let me just clarify that I believe the late-Sengoku tōsei gusoku ("modern armour") is comparable to munition plate of Europe in the 16th century. However I am saying that while not being very knowledgeable about the actual defensive qualities of the armours, so I could very well be wrong. Personally I think even the tōsei gusoku is inferior to munition-plate, but comparable in that it is adequately strong (being as strong or stronger than previous armour) while being mass-produced for samurai. Unfortunately I don't know enough about the armour industry itself other than that important blacksmith districts developed in daimyōs' castle towns throughout Japan, where large quantities of arms and armours were ordered and produced.

According to the early Edo era source zōhyō monogatari, ashigaru wore a cuirass with the stereotypical haidate (the skirt-like thing). These were usually made out of rectangular iron plates placed sown together, though the torso and back part were often laminar (as zōhyō monogatari depicted). On their head were jingasa (black hat that is kind-of shaped like the traditional Asian conical bamboo hat, but made of metal, though in earlier periods it was likely not metal), some kind of rudimentary hand-arm protector that I don't even know if qualifies as gauntlets, and no leg protection (so it also recommend attacking the arms and feet with the sword). I don't actually know how that would compare to infantry armour in Europe, though it seems similar as well.