You're in luck. If your antenna is good (the expensive part) then all you need is the little amplifier that pumps up the signal on its way into the TT. You're also lucky that Jensen told you a Winegard would work. Here's one, cheap and easy!: http://www.amazon.com/Winegard-RA-72...gard+amplifier
Replacing the roof-top antenna, especially for a different brand with a different mount, would present far more challenges. Had that been the case, I might have suggested simply mounting a home-type antenna on a pole, and zip-tie it to the TT when camped. Thankfully, you can avoid this!