http://www.championtrailers.com/index.html

http://www.southwestwheel.com/

You might try these guys or at least be able to get some ideas off their sites.

You should have a good parts store and counter person near you. they can get your brakes relined about 3 to 5 day turn around. he should be able to cross your brake cylinder to replace it. hope this helps

Championtrailer has everything, and their reasonably priced, used them a lot for my old trailer.
Also dexter axle has a very helpful site(a lot of boat trailers have Dexter Axles) with diagrams and part #'s , etc.

http://www.dexteraxle.com/

Well I did the Napa thing and they had everything I needed.

Thank You Gentlemen