Any "toy" TX with PPM output?

I'm starting to build a plane to be used partly as a trainer for my 5yo son, with the intention of being able to throw over dialed-down throws or possibly even mix his controls with my master (another thread perhaps)
Anyway, I have a spare devo 7E and gave it to him and he was quite excited at the prospect, but then he picked up the TX from my Cheerson CX-10 and started messing with it, and it struck me that an even smaller "toy" TX would be even better suited. So, does anyone know of such a TX that either has PPM-out as standard, or could be hacked to find an internal PPM stream? I'm talking something that can be bought as a cheap (sub $50) RTF package, preferably with a vehicle that can be controlled with a modded devo?

Plane will be a modded " FFF Eagle ", planning elavon and v-tail, modded, streamlined and extended to be a Wedge Tailed Eagle (aka. Wedgie )