I have a dicapac, its good for snorkeling and other shallow activities, and it can fit nearly any dslr, plus it is cheaper. I took this picture with it, but you would probably want something more substantial for your needs. I would look at some of these:
http://www.bhphotovideo.com/c/search?atclk=Depth+Rating_330%27+%28100m%29&Ns=p_PRICE_2%7C0&ci=16477&N=4185679681+4283022103+4209935407+4209935409+4283022084+4283022083+4210544121+4279891319&mnp=&mxp=500
if that doesn't work, search for the ewa-marine u-axp or u-bxp, they both go much deeper than the dicapac that I have, but are way cheaper than a camera specific housing
heres the picture I took with the dicapac s10 (camera was a gh2)