I replaced my OEM b/w camera with one of these:
RV Cams ADTH Replacement Kit
It was pretty much "plug and Play" with using the present cables and power, but it left a little to be desired as far as installation instructions.
I'd contact them and ask what they would recommend.
Here are a couple of photos of my install. I'm sorry the dash is dark but it fits in the dash console where the old video tube was. I had to mount it outside the hole as it is bigger than the OEM.