The rubber for the belly band is an off-the-rack purchase at any Rv parts store/website.
Per trailer-specific parts:
That one's tough since the trailer's been out of production for years. Is the rear window missing altogether?
Some parts may be available from
Trilliumrv, since the Surfside's based on the
Trillium and they do carry some replacementparts for early trailers....post some pics of what you're looking for (especially rear window) and we may have more suggestions.
Trillium sells exact duplicate door hinges for the
Trillium brand, but I think
Surfside used something different from those used on the Trillium. As I recall, though, Surfside also used
refrigerator hinges and they're probably still available at
websites that sell such things.
Francesca