Yeah. We have lathes. I was just looking on McMaster to find the broach and bushings. We have never broached key ways before but it doesn't look too difficult.
Any concerns with mounting the .500 in Hex directly to the CIM shaft?
Here is what I think we would need to buy in order to broach correctly:
8mm reamer-
http://www.mcmaster.com/#8851a23/=10a37ir
2mm keyway broach-
http://www.mcmaster.com/#8805a11/=10a3730
8mm collared bushing-
http://www.mcmaster.com/#8804a71/=10a36rr