[Greasey Harley]

Why not just have a reputable machine shop build you an engine?
You can specify parts: pistons, rings, gaskets, heads, cam, bearings, etc.
You can also spec compression ratio, quench, deck height, etc.
You can have it made any way you like, and you'll know exactly what you have.
Usually cheaper than a "crate motor" and most reputable engine shops will warranty the engine if they build it. It also supports your local economy.
Just a thought
-Russ