Stroke old 340 or new crate engine

trying to decide what to do with my 1970 340. I'm getting ready to pull the engine and trans from my prostreet duster. I can't seem to decide wether to rebuild it into a 416-420 or just buy a crate engine. I'd like it to make 500hp normally aspirated and possibly install a troque storm supercharger. If I rebuild the 340 I can get a compression ratio thats more suited to the supercharger. Crate engines seem to be around 10:1. Also seems like most crate engines I've looked at use cast cranks. Seems like forged would be better but maybe its just over kill. Opinions?