Dear OM Chris,
You are right about it being easier for Thai amateurs to operate in the USA vs The rest of us in Thailand
However there is a way around this problem if you ask the R.A.S.T. to help you get your documents BEFORE you leave home on a trip to Thailand.
Just check the RAST homepage on http://www.qsl.net/rast/text/LicensingAug6_03.htm
and you will find all the information you need to get on the air here in Thailand without any problems.
The even post a lists of approved rigs
I have read accounts of people who did it this way and had no problems when the came here.
Brian PE1RLQ Thailand