I would look at using a set of 440-1, the best I could get, as long as I could buy either a set of TTI or maybe a custom set of Hedman BB A body fender well headers from their race shop to fit your car
I made 775 HP using Oregon 91 octane pump several years back using a set of ported 440-1 heads on my old 518 C.I. 400 C.I. stroker motor short block with a 400-3 intake and a 1050 CFM Holley Dominator #9375 non HP carb. That was on a DTS engine dyno in Klamath Falls, OR at 4300 ft. elevation