We searched for the GSI stove manual last year when we bought our Sabre and couldn't find it. Like I said in my previous post, we just happened to find Sure Marine and they were helpful. My wife started going through all the boat paperwork again after this topic was posted and low and behold, the stove manual was filed in the Westerbeke manual!
So, I do have a manual; it's for a 2 burner range gimbaled model GS-2331. It lists Corp Brothers, Inc in Providence as a GSI authorized dealer. I can't post any pictures of the stove, because I am recovering from surgery and probably won't make it down to the boatyard for another week.
Let me know if this new info helps out, I could fax you a copy of the manual if you would like. I probably would have found my misplaced manual at some point, but thanks to your post, it helped me find it sooner!