If the monitor and wiring is still good, you might check Ebay. A new rear vision camera can be had anywhere from $12 - $50. A new 7" color dash monitor is about $35. I replaced the old B&W 5" CRT monitor with a 7" color LED. For the price of your deductible, you could have a whole new system. Since my new monitor had 2 inputs, I added a right side camera to check my blind spot when changing lanes.
Bob & Donna
'98 Gulf Stream Sun Voyager DP being pushed by a '00 Beetle TDI