I bought this off UKV from a guy named styl3r a while ago it uses 2 x 18650 batteries.

The 510 thread needs some fixing but it works most of the time, when it gets hot the glue softens and that's the only issue.

details:
dual 18650 vv mod "TTS"

https://www.dropbox.com/s/85yurgjwb6...2021.52.00.jpg
https://www.dropbox.com/s/js59tmv9ua...2021.51.25.jpg

$40 plus post