Just got myself 8 AAs (Rechargeable) from IKEA for my custom 9,6 V battery pack which I use for my Nikko Super Cruiser. A bit overkill when you count the capacity lol. :
NIKKO 9.6V 650MAH battery pack and charger B01565 in category Gadgets - Hobbies/RC Models at Easy Technology.
Nikko 9.6 Volt Rechargeable NiCd Turbo Battery 1296 Red Pack 12068012994 | eBay