Same deal here. One place said they would do it when I mention screw in studs, but estimated $400 for the axles and drums. I just ordered some custom steel wheels for around $250. Considering the axles already had green bearings on them, all new brake hardware and wheel cylinders, I figured the wheels were a better option for me.
Hmmm, when I took mine in they shot me down. Mine had the three holes in between the studs and the machine shop measured and there was no way to do it. I could have run 4 studs, but not 5.