Where are you located? I have an engine (albeit a bit grungy) out of my 85 Sun sport. Its the 351W. I’m not for sure when, but the block at least (maybe the heads too) was at one point a reman, and I had it running a couple of weekends ago.

I just stumbled upon a whole parts boat with a cleaner engine so I swapped them out. Oil was black when I drained it, no particles or milky coloration even though the boat has sat for 3 years.

This one needs cleaned up and for sure intake manifold gaskets, and just a little love, but it ran fine.