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. :
NIHM 6.0V GIGA Pack | bol.com
Nikko 6.0V Volt NiCd 4 Hour R/C Battery and 50 similar items