Kroll,
There has been several threads on this same subject posted on the Rockwell Lathe group on Yahoo. Pretty much what it comes to is you have to machine off all of the existing gear teeth, down to a certain diameter. Then buy a stock gear from Boston Gear or Martin, bore it out for a shrink fit to the turned diameter on the pulley. Don't need much, about .0005" to .001" interference. You have to do likewise to the mating gear, too. The teeth count for both gears change, too. I just notice, you have a thread going on the Rockwell lathe group for this. Anyways, this is just about the only way it's going to get fixed other than building from scratch a new part.. There is nobody out there providing repair parts for these lathes nowadays.