Polish embassy needs from Poland a document stating she is allowed to marry overseas, she must go to her embassy in Bangkok in person and apply during working hours of M,W,F between 9:00 am and noon.
Fee is 1598 Baht
and is provided on the spot, and they type it.
Since you wish to register your marriage your bride will have to supply her Polish embassy with a document from her home country stating she is entitled to marry overseas, The name I forget because is a long name in polish but her embassy is very helpful and tell will tell her in Polish if she contacts them. There is an embassy fee of 1,598 baht and she must go in person during their normal working hours of Monday ,Wednesday, Friday between 9:00 am and noon. They will write a affidavit for her on the spot.
Their website is in mostly Polish so maybe they have in the Polish language but I know is not in Thai or English.