@fincham@cloudisland.nz in the past I would have suggested “Mr Positive” (battery distributor in Auckland), but it looks like they’re gone. (I last bought things there in 2020.) As best I can tell they were Positive Imports Ltd, which still exists as a registered company, but the web presence seems to have been broken since about August 2025. So… if you do find a good seller of high quality 18650s, then report back :-)