A guy has a bunch of them up on Ebay, starting at $350 or "buy it now" for $400.
They use (and include in the price) the Toki 18 engine with pull start.
No real need to balance the stabs on a plane that small. It probably will not go that fast. Just use a good servo.
The thing is...imagine how much MORE lead it is going to need in the NOSE to balance out after you put six ounces of lead in the tail!
I built an Aeronaut Vampire with a tokifan, and it needed nearly a pound of lead in the nose to balance. It did get airborne, but an extra pound of lead on a plane of this class is totally unacceptable, and the plane needed to be totally stripped apart, re-thought, and re-worked, to eliminate ANY lead for balance.
I recommend you start taping equipment into place and establish how far forward you need everything to be on your F22 before going too much further. Which kit is that, the EAM one?