I too am looking to swap in a new battery in my laptop. and not sure best place to source one. according to razer, i think i read that they don’t want you to change out the battery yourself. 

although I don’t think it should be much of an issue to do. i found a battery for the blade 14 on ebay that i’ll probably just order and try to swap it myself or at least have a backup battery. not sure if really need to change it but the current battery life is not very good right now. curious if a new battery would improve things or maybe that’s just the expected battery life on this particular machine.