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 6V Slide Slot in Battery 1262 - Etsy
Make your own RC Car Battery Pack or Repair NIKKO Ni-Cd 6.0V-620mAh – Видео Dailymotion