The Nissan Path

Does anyone know where I can get metal or chrome tire valve caps? I bought a set from eBay, but they are plastic. I want genuine Nissan valve caps that are not plastic.

I bought a set similar to these, but they were fake.
http://i22.ebayimg.com/03/i/000/a7/d7/ff74_1.JPG

I have even checked Nissan's website but can't find anything.

I haven't seen any Nissan valve stem caps yet but here are a couple of what look to be metal types with the Nismo logo;

http://www.nismoparts.com/catalog/?section=1222#1668

http://www.mynismo.com/products/Default.asp?id=3740

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