You may get lucky and find the LED lighting you need here.
While researching another item for our Sunseeker, A service rep told me about this site and that they offered the product I was looking for. He also said that they are a major supplier for the RV industry and that they did retail sales. Another didbit that he added was to call them to place any order because their online shipping price calculator is way off and to disregard it.
Hope this helps
If all else fails, call the RV manufacturer and ask them where you can get the part.
As far as just cutting the wires and hooking up the new led light goes. Make sure you determine the polarity of the existing wiring i.e. + and - and hook up accordingly, There may be a diode in the light fixture circuit that will protect if if it is hooked up backwards and then there might not. If there isn't and it is hooked up backwards, you could fry the new fixture.
Remember every electrical device contains "Magic Smoke" that must not be released, for if released, it will quit working.