Keep in mind the windsheild off the outboard is a '72 model which is a different style cap than your '78 model. The earlier windsheilds had a larger center panel, I don't know if it work or not.
$150 sounds
pricey(
) to me for a used windsheild off a boat he's about to take to the dump.
$150 should buy you the entire hull in my mind.