Nikko 9.6v battery pack and charger substitution set.
Nikko 1764B 6.0v NiCd Battery 4 Hour Charger for sale online | eBay
Nikko 6.0V Ni-Cd Battery Pack Quick Slot Charger 4 Hour Toy RC Radio Control | eBay
Amazon.com: Tenergy RC Battery Charger for 9.6V (8S) NiMH/NiCd Battery Packs, 12V 400mA AC Plug Charger w/Standard Tamiya Connector for RC Hobbies, Not Compatible with Spike The Dinosaur : Toys & Games