What's the rest of the camper look like? If the camper is in really great condition and presents well, everything works, etc, then I would go ahead and do the re-caulk and sell it like it was meticulously maintained all through the years. The material won't cost you that much and you'll get top dollar from a buyer who is ready to put it on his truck and go camping.
On the other hand, if there are other issues such as items or appliances that don't work, faded/yellowing exterior plastics, interior is looking tired and worn, etc., then I would sell it as "needs some TLC" and let the new owner take care of the caulking as part of whatever other mods it needs.