Since the shafts seem to only be hardened in specific locations, I don't know if something with uniform hardness would be suitable. Probably so, but we're getting into territory that's way beyond the average back yard tinkerer's capability. Normally, machining of precision located holes is done on "soft' (annealed) metal of the proper alloy, and then it's hardened afterwards, with a final grinding operation to achieve the proper dimensions and surface finish. That's professional shop territory, not a "Harbor Freight drill press" operation. Just my opinion- - - -that, plus five bucks or so will get you a cup of fancy coffee where the man bun wearing, bike riding, spandex shorts crowd hangs out!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!