If you haven't tried one on - you probably should do as cadiver suggested and go purchase one from your local dive store. cadiver should mention he has a vested interest in this as he is associated with a dive store.
Otherwise a search of the usual suspects like LeisurePro should turn up.
One thing you SHOULDN'T do (and I only mention it because others on the board have admitted it in the past), is try one on for size at a dive shop, then buy online - very unethical. It costs the dive shop time and money for one of their employees to assist you, they don't gain a sale, and it adds to the burden of doing business. People complain on here that they get banned from dive shops because they show up with the same brand new BC they tried on in the store two weeks earlier.
Reminds me of a family I saw in a book store yesterday - the father was looking at a book he was going to buy, and his daughter said "don't buy it Dad, we'll go home and order it from Amazon - it's cheaper". Which begs the question why they even went in the book store in the first place.
cheers