Find a Cross roads dealer in your area. I am sure they can get you the factory replacement. Or call one and have it shipped. I had trouble with the rear ladder. Finding the exact replacement. A local dealer can get me one.
Yep call Crossroads and they will conect you with the right sales person for your area. They can ship almost anything. The nice part is it is origional and will fit.
I had to get two body panels, a fender, and a new wheel and they had it all and could have shipped it but it would have cost more than the new parts so I went and picked the parts up at their office. Best part is it all matches perfect and they answered my questions while I was there.
Parts are a story but you can guess with a fender, wheel, and body panels.
Great service
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2002 Dodge Ram 4x4 Long Box Extended Cab Diesel.
For the wall switch you might try a good auto parts store. They are 12 volt switches.
Home depot or Lowes may have a sink to fit. Or you may want to upgrade to a better sink. Household sinks & faucets work fine in RV's. I've replaced several over the years.