I Need a Slant 6 Ventura county

Hey Everyone,

I thought I'd introduce myself.
I just purchased a 65' Dart the cleanest car ever! I seriously think the engine may be original (like from the factory) no wires have ever been cut (not even for a radio). Daily driver before engine quit working. I definitely have a blown head gasket, and one of the cylinders isn't getting compression. Nonetheless, I'm lovin' it! My big bright idea is to find a Slant 6 to put in it while I rebuild the engine...whadda think?