If you are wanting a flash to go on your camera (and be compatible in terms of automatic flash metering), I might suggest the Canon 270EX, which is over your budget. Ideally, I'd suggest the Canon 430EX, which is much better but even more over your budget.
There are some 'off-brand' flashes that are compatible with Canon cameras, but they might be hit and miss because they have had to be reverse engineered. Also, the build quality probably won't be as good as a Canon unit.
http://www.bhphotovideo.com/c/search?ci=647&N=4294204366+4293918168+4294955935