Wow, those are very different. My 10" Campys are the same as the Left wheel and they are from a 1976 Euro car. This photo shows the same wheel as the right side and looks like it might be a Euro GTS, but of what year, I'm not sure. I agree with Mike that it is probably an early variant as I've seen way more of the ones I have.
Good luck in the hunt!
Mark
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