I spent several years running the connecting rod reconditioning department of a machine shop where we specialized in crankshaft welding, straightening, and regrinding. Repairing just the snout of a stovebolt crankshaft would be in the $200.00 range, as two separate operations would be involved. Item #1 will be the Woodruff key slot- - - -inserting a solid copper key and building up the surrounding area with weld material to tighten the clearance, then recutting the slot to accurate dimensions. Then the press-fit area of the crank snout would have to be welded up and ground back to the proper diameter. Then any regrinding and/or polishing of the bearing journals would need to be accomplished. Little if any balancing of an inline 6-cylinder crankshaft is required, since it's almost perfectly balanced by the 120-degree separation of the counterweights. If it is spun up in a balance machine, no bob weights are needed to simulate the weight of connecting rods and pistons like is required with a 4 or 8 cylinder crankshaft.

Stovebolt crankshafts are listed on Ebay every day. Even with shipping, that route would probably be less expensive than major surgery on the snout of the crank in question.
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!
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