I have 4 18" factory polished bullitts with the stock BFG KDWS 235/50 18 tires for sale. They less then 8k easy (no burnouts, abuse, etc.) miles on them and have been sitting in storage since may. Center caps are NOT included. Asking $650.
However, I used to have the same set and sold them back in May. To be honest, I think you can do better than $650 even without the caps. Try Craigslist. I got $800 for mine.