Doesn't sound that hard to duplicate all that functionality on a card.
Arduino Uno
Motor controller shield
3A motor at 100:1 gearing >> offboard? connector only?
7.2V battery pack >> offboard? connector only?
Wall charger
Memory (need about .25Gig, currently using SD memory/SD shield)
If you're interested, PM me with more details of your design and your goals, I can quote you a price to design it up with a PL from mouser.com, digikey.com, you can chase qtys with a turnkey production house.