In case it helps anyone. Samut Prakan immigration (which is now located in the newly rennovated Pak Nam office) accepts the following documents for 60 day extension based on marriage/family.
Copies of the following all signed and notorised:
- marriage certificate (in case of wife)
- birth certificate (in case of dependant/child)
- tambien baan of wife/dependant
- ID card of wife/dependant
- all passport pages with ID and stamps
-TM 30 Receipt of notification copy (make sure it's date-stamped from when you last entered the country, they flagged this with me and I got a telling off for not reporting 24 hours within entering the country)
-1900 baht
-wife/child in person as they want to take pictures of you as a couple/family
-passport photo for one of the three forms you have to fill out
Not needed contrary to other reports/offices:
* Kor ror 22, you don't need any copy of this, whether it is old or newly updated.