Demand and Supply

If my post was over your head.
Guys send trucks to the Junkyard with 318, and 360 both LA and Roller camed one's due to rusted bodies, broken rear end or trans.
And especially vans. Vans take work to get one out.
Smart guy would hit the lower cost junk yards and YOU Pull It's. Grab. One and build it, so has one ready fir his dream car.
Start with pulling the intake and head and look see as well.as measurements. Even cheap Harbor Freight will do.

Only then will you know if the heads need junked or what Pistons you need.
Everything else is just dreams.
Even a car guy like me sent a running driving 360 roller motor to get scooped up or scrapped. I can't save them all.