Both Singapore and Malaysia have excellent birding opportunities. A little research will lead you to best locations.
On this forum look for the work of KHOR - who often posts shots from the Malaysia area. He might be able to provide you will some shooting location tips via PM?
I just got back from Singapore. They do have the famous Jurong Bird Park where you can practice your photography skills, the birds are free flying in big aviaries, mostly not caged. . It's an 'all you can shoot' buffet. Just watch out for moisture on your lenses since Singapore is almost on the equator, weather is pretty damp/muggy. I had to clean/defog my lenses and viewfinders for the first 2 hours everyday.
I could imagine Thailand being good though 