Here is a great shootout of budget SBC heads heads, and the baseline engine has the heads you have. We've built a couple of engines with the Patriot heads in the article, and they flat out work. They've seemed to hold up well, and are good quality for the price. The Edelbrocks work well also, and I'll some guys put a whole bunch of miles on them. Considering the price of the Patriot, Jegs, or Summit heads, I would not buy Vortecs either modified or having them modified to run a cam over .480 lift and having to buy a Vortec intake as well. They are good heads if you already have them or getthem dirt cheap, but aluminum heads very reasonable these days, and you can run higher CR without detonation than with iron heads.
http://www.carcraft.com/techarticles...head_shootout/