I was able to get a fiberglass part from Mobilife RV Centre in Canada for my 2000 Dodge Roadtrek. They had bought a bunch of old Roadtrek parts at auction during the bankruptcy. Check with Stephanie in their Parts Dept. at 519-653-5788 (Canadian #).
From what I have heard, the molds for the older Roadtrek body parts are still around and might (eventually) be used to manufacture them new, but when and by who is not clear. Check out the following link: