Issued on the spot.
As mentioned available at airport.
Simple process at airport.
In list below disregard TM6 (unless you have one.
At BKK they do they do the form etc 200b
Passport and one copy of first page, visa page, lastest entry visa, and T.M.6.
Application form T.M. 8.
1 photo (4x6 cm)
Re-entry permit fee (1,000 THB for single entry/ 3,800 THB for multiple entries)