For the amount you want to spend, you will not get a reliable truck and camper, you would only be able to get a project to do repairs on most likely.
Second option I would rather tow a Tab with a Subaru than 2wd B or C if what you're looking for is relaxed driving in the snow.
BUT- if you stick to wanting to boondock and take winter showers, probably the truck camper -and a well insulated quality one- is your only option listed. Very few travel trailers, B, or C units will have insulated and heated tanks.
I believe you will have to compromise on your budget or your wants.
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