My wild guess is Amazon Miniatures. They had an impressive range of heads, weapons, shields and other bits. I ordered a bunch of this-and-that back then. A lot of that obviously remains in the bits box untouched, but that's fine because the company has apparently closed so no chance of replenishing any time soon. There's some discussion of its fate elsewhere.
They had Qin heads, Chinese heads, Mongol heads and much more. If it helps at all, pdf catalogues can still be downloaded from
archive.org. Of course, those replicate their website images which were a baffling mix of passable photos, line drawings, blurry 5x5 pixel scans of shiny tin, and nonexistent. Maybe I shouldn't blame them. It was a small business with thousands of tiny bits from multiple sources (including, for example, Garrison miniatures which allegedly date back to 1966).
Their site also contained a lovely
list of weapons. Always good to know that Shi Ba Ban Wu Yi is the skill in wielding Shi Ba Ban Bing Qi, which comprises Dao, Qiang, Jian, Ji, Gun, Bang, Shuo, Tang, Fu, Yue, Chan, Pa, Bian, Jian, Chui, Cha, Ge and Mao. Maybe I should download personal copies of everything, just in case...
(Is that a Ji in the pic?)