Jeff this might sound a little far out, but a lot depends on just how serious you are about the restoration. I've had to fab quite a few parts for my 3604 and fortunately I didn't have to make the ball studs. I don't have a hardness tester but I gave the old studs a file check in several places and they are soft to the file so that tells me that they are not heat treated. This is not a terribly difficult part to make for a job shop that has CNC equipment. I would bet that if you took your old parts to a job shop they could fab you new ones from 4140 which would be as good as the originals. The program for this part is very simple and a qualified shop should be able to knock them out in an hour or so. Once the progran is written making the part will only take a few minutes of machine time. You night even see what they would charge for a dozen or so and sell them off to offset the costs, might even get yours for free after selling the extras. I’m sure you aren’t the only one that has had this problem.
Denny Graham
Sandwich, IL

Denny G
Sandwich, IL