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These are very unusual d10s.
(i.imgur.com)
They roll almost as nicely as the aulde skhoole d20s numbered twice, by my testing seem to be more than sufficiently random, and are pretty good conversation pieces when you pull them out in a room of people who've never seen them before.
I got them from Taobao. I can't imagine that they're only available in China, though.
I'll do some research and see what I can find. I haven't found anything exactly like this yet, but I've found similar style D10 on Etsy though, so I'm sure I'll find them if I keep digging
In style they're very similar to ancient Chinese d18s, so ... it could be that these are actually Chinese in origin.