big block crankshaft cant find numbers

[indyjps]

got this in a 454 marine block, pretty cool block all 5 mains are 4 bolt as opposed to the center 3. casting # is N353089 i can find a 353039 listed as a cast crank, this is steel and the N in the casting # is something ive never seen before. my best guess is this was an over the counter marine/racing short block. crank has one journal thats in bad shape dont know if its worth having the crank welded, or just turn down and see how it finishes out. ive got an oven @ work that heats up to 700 degrees for weld repairs on cast iron (tool and die shop) it drives me crazy that i cant get anything in there. thanks for any help.