I got these Cragar SS wheels made to my specs ( width & back-spacing) for about $100 each at a place called Collins Tire and Wheel, in Lakewood, California.
Wow! When I checked with Newstalgia Wheel, who was reproducing the Cragar wheels about a year & a half ago (maybe longer?), they said it would add about $50 per wheel to get a custom offset. Would have pushed the price over $200 a wheel IIRC.