The melody, as charming as it is, was written by Richard Rodgers, and is not a Thai melody, and probably would not mean a whole lot to Thai audiences, with exception of the ones who were familiar with the show--

I have an arrangement of the a Siamese march that apparently was used in the real king's court, for the entrance of his children--however, the arrangement is for two classical guitars, and, given that it is based on a piece from the last century, may not mean a lot to Thai listeners--PM me if you are interested--

Sorry, I am on the wrong track--you're post is a bit unclear, and I thought your band was going to Thailand--apparently it is the scouts who are going to Thailand--in that case, get your e-mail address to me, and I can send a PDF of the fake sheet, dots and chords in the Key of F--