I was at the Brewski Sky Bar last night and the "pints" there are 470 ml (so I stand corrected.)
About 10-12 different beers on tap and over 100 different varieties of beer when counting bottles too. The 200 thb special was Maha Nakorn, a Thai craft beer of the wheat beer variety. (Pretty good, actually.) Most of the other "pints" were in the 260-300 thb range.