My 2006 Sunseeker 3100LTD (31 footer) came from previous owner with a wireless receiver made by VR3. Their website here -
Wired / Wireless Back Up*Cameras
shows what looks like my unit here - VRBCS335W - Wired/Wireless Back-up Camera System
Unfortunately the label with the model # is worn off of my receiver.
You might give them a call or an email and see what a receiver unit might cost to replace yours.
By the way, I prefer a good "ground guide" to tell me what is directly behind the unit. Wife and daughter are slowly learning what to do... I keep it in case neither of them is around to help out.
Enjoy the coach! We have used ours a couple of times since we bought it last October and have come to really like it.
Chris in Virginia
2006 Sunseeker 3100SS/LTD
2008 Smart Passion Cabriolet TOAD
1986 Honda Helix (Original owner)