[FWB]

it's a marine block, can see on the one side where there is a machine mark thru where the side oiling passage would normally be.
a good uncracked marine block is worth about 1500, so if he turned down 2 grand, shame on him. if its still standard bore, and it looks like it may be by the factory style eyebrows in the pistons, and it has the maincaps and bolts.
offer 1500, if it has been stored for a while without the maincaps on, it may be tweeked a bit. if he wants to retire from selling a boat motor walk away.