Here's a lineup of Edelbrock manifolds for the SBC in your rev range. I'd probably begin with a Victor Jr. and 750 double pumper. Once I established a credible baseline, I might begin experimenting with spacers/turtles.
http://www.edelbrock.com/automotive_...ictor-sb.shtml
I will normally recommend a high-rise, dual-plane manifold such as an RPM if revs are 6500 or less and you're going to use a stall of 3000 or less, but your application will require more manifold, so the Victor Jr. single-plane would be a better fit in my opinion.