Button Cell Battery
From Amazon
GP Batteries GPCR2032-2CPU10 Button Cell CR 2032 Lithium 3V Pack of 10
Conrad Electronic
GP Batteries Button cell CR 2032 3 V 10 pc(s) Lithium GPCR2032STD900C10
OnBuy
GP Batteries GPCR2032-2CPU10 Button Cell CR 2032 Lithium 3V Pack of 10