@PRREnola - If it turns out that the MTH version of the F7 is the one you were thinking of, the one fortunate thing that you may want to consider is it appears you might be able to purchase an AA set (1 powered and 1 non-powered) directly from MTH on their On-Line store, as I just checked this out on line. The product description is…
F7 A unit 20-20559-1 (Powered, Dual Motors, Proto 3.0)
F7 A unit 20-20559-4 (Non-Powered)