A few things that I believe are Sunline specific:
Aluminum siding (Krystal Kote)
Striping and logo decals
Fender trim
I can't think of anything inside the camper that doesn't use generic materials, although somethings will be obsolete like wall paneling, fabrics, carpet, flooring etc.
All of these items can be worked around if need be. We just bought a gently used 2007 2499 and have no concerns about maintenance. Although I do have concerns about siding damage.
Happy hunting and do check for signs of water intrusion. (Hint: start with your nose)
Rich
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1992 T-2470 (now residing in South Carolina)
Current Sunline-2007 Solaris 2499
2018 Silverado 1500 w/Max Trailering pkg.