"The AENL was is a 9.2 HP @ 3600 RPM engine. The "D" suffix indicates these have the valve rotator added to the exhaust valve."
Predator engines (Honda clones) from Harbor freight seem to have a reasonably good reputation, they jump from 8 HP to 13 HP, the 13 HP is under $400. Even has electric start, along with the recoil start.
Might work for you?