2 x CR2032 Coin Cell Battery Box w/ On-Off Switch & Plain Wires : ID 4988 : $1.50 : Adafruit Industries, Unique & fun DIY electronics and kits
Amazon.com: Duracell CR2032 3V Lithium Battery, Child Safety Features, 4 Count Pack, Lithium Coin Battery for Key Fob, Car Remote, Glucose Monitor, CR Lithium 3 Volt Cell : Health & Household
Amazon.co.jp: EEMB CR2032 Battery with Solder Tab 3V Lithium Battery Li-MnO2 Button Cell 2032 Battery for Game Boy GBA and Color (10PCS, CR2032-PCN2) : Electronics