https://www.fasttech.com/products/0/10008963/5302405-fenix-arb-l14-icr-14500-3-6v-800mah-protected
https://www.fasttech.com/products/0/10002180/8482600-soshine-icr-14500-900mah-rechargeable-li-ion
I like the Efest 650mah purple the best, holds a higher voltage under a load. Either of the above should work fine.
Button top and flat top works in my SP10A.