Oh that Winter!, Soon summer now!
If you have the Money, an high end carb With everything adjustable, With replaceable air bleeds and such is nice, especially if youre gonna "supertune" it on a dyno. I have seen how practical this is on the dyno With my own eyes!
If not maybe an "regular" carb would do?
But I Guess you looking at an Holley HP style carb?
I have had a couple Street Avengers and they work fine, but they seem to be jetted a bit on the lean side out of the box, I have also read that on the internet by other users of them. And of course no replaceable Air bleeds and such.
I have an 870 Street Avenger on a 461 Hyd. Roller Pontiac, it has been jetted 4 Primary and 6 Secondary sizes up on the dyno by the previous owner/ engine Builder. It works OK. I have had other Holleys too and they have never given me trouble.
My dad tried Demon/Barry Grant carburetors (some years ago, 6-7 maybe) on a 383 stroker and a 650HP 350 SBC With old Pontiac Cupcar heads, and he think they worked great but they were very far away out of the Box, so there where much more work baselining them and dialing them in compared to Holleys he think, he have since went back to Holleys. Demon carbs looks good though!
Was this more confusing than god tips maybe? Sorry
The cheapest and most fun would probably be like you said, rebuild With New main body. And use some time adjusting it, hopefully not too troublesome