Sweet! you actualy found a pic of an Offy intake with the 4500flange never saw one of those before except for in offys catalog!
Out of the older singlecarb intakemanifolds i would recomend the Stripdominator if you can find one,its the more modern of the ancient stuff,works quite well on a 7500rpm 340 due to having a reasonably sized plenum and not to large runners and therefor works quite well on a small cube engine. Rated for 4-8500 rpm if my memory is right,but it works quite well at lower rpm than that so dont worry about that part,ran one on the street for years.
Edelbrock tunnelram? Hell yes! I would recomend the version with the smaller dual carb top for a variety of reasons but mostly due to the fact that the smaller plenum gives better signal to the carbs,dont let anyone fool you,tunnelrams works! I cant remember what these manifolds where rated at but i believe the smaller top versions where recomended for 3-3500-7500rpms wich is pretty much right in the range for what you are doing. The taller top,was recomended for 5-8500rpm or so if my memory is correct,i bet someone out there is sitting with an old catalog and can correct me if need be.
the single carb versions are not something i would recomend to anyone, Never saw a dominator carb top for those manifolds in real life but those are way out of our league anyway,those are if you go nuts and are at a point where you try to compete with old prostock smallblocks.