Don't rule out a Holley 94 carb! I tried the 81 and the 97 Strombergs, but wasn't satisfied. On a lark, I installed a Holley 94 and I love it! It has good throttle response, a higher top end, good idle, and improved gas mileage, all compared to the original updraft carb. No rejetting was required, either. These carbs and their variants were used for two decades or so by FoMoCo, so there are lots of 'em around and relatively cheap. Rebuild or just gasket kits are readily available on-line.
Marshall