You might check with a local machine shop and see if one of their suppliers offers welding and re-maching crankshafts. Only forged cranks need apply. Cast cranks won't weld and turn down. Had a 454 Chevy that qualified. Was welded up and turned back down to stock on all mains. It was not really that bad in price. If you just have one main or throw that needs welding, it should not be too much......maybe. The world has turned over a few times since I rebuilt that 454......but gosh, was it a runner....over 600 ft. lbs of torque and 530 hp. Ole SPARKY would fly with that engine in it.

Regards

Runem
1983 300SD - aka - SPARKY THE DIESEL