Interesting that you didn't consider Ebay first, craigslist second, then a very very distant third, dealer. The chance of scrapyard having the part you need, when you need it, is about zero.
Heres a good ebay search:
2010 camaro wheel polished
http://shop.ebay.com/i.html?_nkw=201....c0.m270.l1313
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