Well, I just broke my 360 block. Terminal?

Cracks in cast iron need to be drilled. always. If the end of that crack isn't drilled, My guess is it will probably get bigger and bigger. it's impossible to tell how long that could take though.

I would be very skeptical about bronzing something like that and expecting to retain the correct machined tolerances when assembled. too much heat and also too much material to remove afterwards.

You MIGHT be able to drill it and fill the hole with jb weld and CAREFULLY file it flat/smooth and get it within a pretty fine tolerance by measurement with a dial indicator.

just my 2c. No guarantees!