Here's a new one that might help someone:-
Thai Embassy In Riyadh Saudi Arabia.
Non-Imm O based on Marriage to a Thai National.
Postal applications accepted. Visa fee 750 Saudi Riyal.
Required documents on the picture below. No proof of funds or bank statement required.
I had to use DHL from Al Khobar which was 160 Saudi Riyal each way. My visa is on the way back to Al Khobar with DHL.
They said they've issued the visa, but I'll have to check once it arrives that it was the Multi Entry Non Imm O that I applied for once it gets here.
TLDR : Answer Summary
The post provides details on applying for a Non-Immigrant O visa based on marriage to a Thai national at the Thai Embassy in Riyadh, Saudi Arabia. It mentions that postal applications are accepted with a fee of 750 Saudi Riyal, and highlights that no proof of funds or bank statements are required. The user used DHL for sending their application, costing 160 Saudi Riyal each way, and is awaiting confirmation of their Multi Entry Non-Immigrant O visa.