There are only two Thailand surgeons for FFS I would recommend, based on the results available. That would be dr. Suporn and dr. Chettawut, and both of these are within logical prices. Logical price for FFS is between $20,000 and $30,000 USD, depending on procedures (and exchange rate). You need to choose a FFS surgeon based on what YOU need for your face, and choose between surgeons who have compatibale skills with what your face needs. You need to have understanding about procedures and details, and research each available surgeon individually to understand what are their strengths and what aren't. Choosing a FFS surgeon because of low price, ignoring all the important reasons, is playing russian roulette with your face, with 5 bullets and only one empty chamber.
If there would be other Thai surgeons for FFS, with the results available to prove their expertise, you wouldn't have a problem knowing about them. And price would be reasonable with that.