I'm sure he could do the aging on a normal black U-42 where he'd have problems is finding a brass/bronze stem and the lock on the opposite side of the case.
Having said that , I'm sure I have seen a black "special edition" U-42 rep that had a gold or brass colored stem on it. It was probably a cheap alie type rep but it certainly would be a start. I have looked to find that rep with no success.