Bras Basah. Just opposite of Swee Lee. Swee Lee also has some drum bags but I'm not too sure of the brands and price. If you're looking for something better, you can call up Nigel from Drums Resources to get Protection Racket cases. That will definitely be out of your $30 price range though. Do know that the snare bags that they carry are all of standard sizes like 14"x5.5", 14"x5", 14"x6.5"... not sure if they have 13"s but a 14" will fit a 13" snare just fine.
Just stuff them at the edge so the snare won't move too much
However just to tell you I have never tried the above before with a snare drum, so I'm not responsible for any damages or whatsoever, do it at your own risk