Japanese (I think) vehicle tag, what is it?

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Came from a collection of tags that were picked up in Europe (I'm including a pics of the whole tag collection), and I'm guessing and the vet traded for this one, because it obviously came from the far east. Anyone here have a clue as to what this is off of? I certainly hope so, otherwise I'm completely lost as to what this is?

Thx in advance.