Don't know where you are located. So, I don't know if this is going to help you.
Try a Craig's List search for your local area. I bought an Even Brake from a Craig's listing locally for $400 simply because neither the seller or I knew how to test it correctly. It works great and I got a Falcon II tow bar included for that price too.
Try this first: craigslist.org
When I try this I always get the Sacramento Craigslist probably because I have a cookie set for Sacramento, which is here:
On the right side of a city listing is a list of other craigslist locations, search through for a location near you.
When you get a city near you, look under the 'forsale' list click 'rvs' then type brake into the search box, select the 'title only' box and then click search.