Look in the WALMART TV SECTION. They have a big assortment of the TV swing out MOUNTS you are referring to that fits the four screws behind the TV monitors... The new TV's are lite-weight now with LCD screens etc...
This may bring up a question for you about leaving the HDTV sets in the trailer when the WX is below freezing... My trailer is a POPUP trailer so I bring mine in but alot of folks leave their's in the big trailers - They say to warm up the trailer first before turning one on... I guess they worry about the LCD screen possibly cracking ???
Roy Ken