I'm thinking probably a battery like this...
would fit in battery compartment.
The only thing is, I can't find these anywhere without buying them bulk.
'Cause I'm thinking them "over the counter" Duracell; Energizer, and other brands of rechargeable batteries at Wally World would cost a lot.
My last effort here for any toy grade RC that uses AA batteries and you must have rechargeables...
All-Batteries.com And then one would have to add in the cost of a charger
.