wah banyak options ni.
kayfuns/russian  if you prefer mouth to lung hit
if you more towards lung hit/ nak byk vapour as well, check out billow, uwell crown, goliath, zephyrus, goblin mini, herakles, etc should be more if others can chime in

Jaya supermarket level 4, kedai handphone/vape..

http://www.lelong.com.my/original-uwell-cr...7-01-Sale-I.htm

EDT:
disclaimer: i remembered seeing the tank online when i was looking for shops that sell this tank. pls ask them first by calling them through phone numbers in the link. also ask whether they sell the rba base as well. the shop is located on the same floor as vapekulture at jaya shopping centre.

Ur cotton is too thin.U need a thicker cotton. Spitback is common if ur cotton amount is not enough. I suggest you change the cotton.

When was the last time u changed ur OCC coil?If it's more than 2 weeks or so i suggest you to get it changed. Besides that, use a tissue to cover ur drip tip then flick ur tank a few times up and down and see if there's still spitback.

Try fire higher

did close the air hole before u take took off the cap for refilling?