I could not find the right battery for my 3 Plus and ended up buying cells and re-soldering them into a new battery. Bought 3 of Panasonic 18650 Li-ion NCR18650G Japan 3600mAh 3.7V from Orbtronic. Used a process similar to described in this video to rebuild the battery - https://www.youtube.com/watch?v=ZXiMgPBA...

On 3 plus model the third screw is not under microSD card but rather under a small sticker on the right side. Plus has longer battery.

I used this you tube video to remove camera and disconnect cables on my 3 Plus version. Don’t use the brute force to remove the battery on the cables side as shown in that video - cables can be damaged. Work out the hinge as recommended here this is the right way!