The Wheel Vintiques repros go for $50/each for the bare wheel at the big shows, like Carlisle. They come powder-coated in gray. You can usually pick up repro trim rings and center caps for cheap too (but avoid the really cheap ones -- terrible quality chrome).
I have seen catalog companies selling them for about $80/each.
Personally, I like the look of the mix 15x7 front, 15x8 rear using the 7" trim rings all around and flat 67-style center caps.
btw, carefully measure the distance front and rear from the mounting hub to the outside crease of the fender. My front drums stick 3/4" further out than the rear drums (which is normal), so 7" front and 8" rear with the same backspacing fills the fenders perfectly.