What you could do is just call the UA res line for general members a when you talk to some person name Sean O'Malley from bombay he can recommend his cousin Rodger who has a shop in BKK......

Sorry for the Pun (jab) but there are many good tailors in BKK . I would avoid Mr. Narry and any in you hotel..

After you get a suit made wander over to Morning Night Bar, their open at 10am and ask for Mona!