k/b perry pumped engine?
I would take that engine and stick it on a Diamond Dust. It doesn't have the power or reliability of the more modern K&B or OS engines. There is a K&B .48 combination for sale now here on RCU. Even the rear carb 7.5 would be a much better choice. You could go for the .91 if you don't mind dealing with the extra weight and fuel consumption.
Mark