Get an IDP, if you have a UK address you can obtain on line through RAC or AA, and then use Express Mail to get it sent out, try and avoid agents they pay bribes and thats starting to make life difficult for those of us who want to do it legally.
DLT offices where an agent will bet your license in a day - there is now a 3 month waiting list in Phuket to get an appointment all because they spotted the gravy train - we now have to drive to Phang Nga or pay an agent (bribe)
I did the same in 2018 no issues then - they have clamped down now, which means somebody gets a good payday same has happened with Cert of Residence which are free, and DLY