The Walbro match for the DLE 20 carb is WT793-1 Another match would be the carb for a ValleyView 20 engine, which is a Walbro. I don't know the carb # though. It may be a 793.
I am well pleased with the "upgrade" I did by replacing the 20 carb with the 30 carb. I only had to lean the low needle about 1/16 of a turn and did not have to touch the high speed needle at all. Transition is much smoother and the drop to idle is instant. I am getting 8210 rpm at wot with a Falcon 16x8 prop. Idle is 1800.
Maybe this will help those that are having similar problems.