Blown Mercruiser 5.0 Alpha. Low hours. Replacement options

[keith]

Pulled the heads and there was rust on the two of the cylinder walls and the valves were toasted and mushroomed. Engine is gone. I am still waiting on prices for 5.7 mpi and 5.7 carb. He is recommending the Mercruiser reman units but doesn't know the availability or pricing yet.