~600 cfm vacuum secondary Holley or Demon. I'm sure that Edelbrock or Quadrajet or Carter of the same size and vacuum secondary would work fine too, but I like the Holley style carb for ease of tuning and they've done great for me. Definitely stay away from that 750 cfm carb you found, way too big and it won't want to work well with a cam that small. Contrary to what was said above, a bigger carb on a smaller engine will tend to run LEAN, since the air going through your venturi is moving too slow to pick up and then atomize the fuel, so you don't get enough fuel. A rich engine is ok, as long as you aren't washing down the cylinder walls with fuel! A lean engine can be very BAD! You can burn holes in valves, burn pistons, all sorts of awfull things!
Stick with a 600 cfm MAX, you could even go smaller if you wanted.
Let us know what you do and how it runs!