I wouldn't be apposed to making it a two piece unit, so that we could broach through it. And/or making it a little longer to that there is enough stock to make the spot where the shaft could enter the socket end... or a bit wider in diameter...
I've planned to go to the EDM machine shop Monday morning and see what they say.
After that I may go a different route, we'll have to see....

Whatever you do, have fun doing it!