Great Planes Super Sportster. If you build it from a kit, add a second aileron servo. I'm guessing you can do some mixing and add flaperons. Or you could add retracts. (Not sure what your JR is capable of.)

Goldberg Tiger 2. Same thing.

Sig 4* (Four Star). Wouldn't recemmend retracts for it, but it could be done.

There are "Sport" warbirds that you might be able to handle okay. These would be nice with retracts, but ask around for one that has a sport wing, not true scale.

Good luck with whatever you choose.
Dennis-