I gotta send my Diploma back to the States for authentication by the Thai Embassy/Consulate there. Can anyone recommend a company/agent for such a task?

Hey guys. I’m sorry if this group isn’t the right place to ask. Basically, I was wondering about the requirements for authenticating my university diploma and transcripts for the purpose of working in Thailand. I’m trying to get a non b visa and work permit. I’ve heard that this must be done through the Thai Consulate/Embassy in the USA. But I have also heard that the requirement can be met with an affidavit from the US Embassy while in Thailand. Which one of these is true? How do you guys recommend going about this? I don’t know when I’ll actually go to Thailand yet but I want to have everything ready.