I was able to get 4 for close to same price although slightly higher off eBay. One of the sellers I purchased from still has some. This is the same mount that was talked about & used in the previous thread. I also was able to make it into a double arm if needed.
Also remember it may be safer to remove the bottom wire holder so it doesn't hit the trailer when folding down as MudDog suggested & done.
Click Here for TV Mounts