I did it yesterday, just to update for those who might ask later (Phuket immigration - Patong beach office):
- Need: passport, visa and stamp copies, filled TM7 form, 1 photo.
- No need: TM30 (I had one, just in case), exit flight booking.
* Arrive few minutes before they open 10am to queue (application done in 10 minutes), and return 1pm to pick it up (done in 5 minutes).
* If you're coming from other area (like me), bring swim shorts & towel - beach is right behind the office 🙂
(mall was not enough to kill 2.5h lol)