Lots of companies offer "top end kits".
Here are some examples from Edlebrock and TrickFlow:
Edelbrock.com - Power Package - Top End Kits - Chevy
Chevy small block Gen I, 5.7L/350, CHEVROLET, Engines & Components, Trick Flow Specialties - trickflow.com
You can research the CFM of the heads and cam numbers, and the details of the other components to see what is involved. Keep in mind their HP numbers are going to be on the optimistic side (gotta love advertising), and unless you duplicate their setup exactly (as in buy the kit) you have no right to complain that your power numbers are not the same, because you changed the formula.
Sounds like you already have a solid shortblock. Buy one of these kits and go for it. Of course this route really takes the fun away from researching, learning, part selection, and truly building your engine. But it is just an option to remove some of the internet forum BS (and no I am *not* accusing anyone of that, just saying).