REBUILD which way to go?

[hankschevelle]

I have a 72 454 with 74 oval port heads, edelbrock intake and 750 holley. It's making 370 hp. It does a pretty good job of pushing 67 chevelle - muncie -3.42 eaton. I just installed electric cut-outs and it sounds like a dump truck with no muffler. Some of the boys in the club have cut-outs and they sound good! Gotta pull motor this winter to fix oil leaks. I want to bump up hp to 425 to 450. Gonna do a cam and new intake. Shud I rework these heads or will they do the job. Engine has few miles, so bottom end should be ok (2 bolt mains) would like to make this around a 2,000 dollar job. Any ideas???
tks --- Hank