Barracuda Wheels

You’re not going to find anything at a wrecker in 5x4”. If your car has been converted to 5x4.5” you’d have a shot, but not 5x4”. There are aftermarket 15” 5x4” wheels, but nothing factory and no one makes that pattern anymore. And I doubt you’re going to get any A-bodies into the yard with 5x4” 15” wheels.

Do not use 5x100mm wheels. 100mm is not 4”, and while the difference is small length-to-length remember that it’s a bolt pattern, not just a single length. You can cram one on there because of the 7/16” lugs you have, as the holes on the 5x100mm wheel are for larger studs than that. But it will side load your studs, and that’s not good.