Well, I was going to suggest Jason talk with
Escape as they do most of the
axle replacements and other repairs for many of the
boler owners and other fiberglasss trailers owners in the area.... but I see he may have already talked with them & doing a major frame rebuild for him is not something they are doing these days. Suspect (or at least it looks to me) that they have a space issue at the shop so they probable do not want to have trailers in for repairs sitting around the yard to long. So most likely sticking to repair jobs they can do a fast turn around on. Axles and
brakes and other minor stuff are done pretty fast by them & very reasonable priced. A total frame and interior rebuild etc would not be a a fast in and out project for them.
I don't think you will find a place that will do ALL the items listed in one location here in BC that I know of. Or if there was you would probable be paying a LOT of money for it.
You may find its cheapest to have a welding shop do the frame for you and find folks who do the other bits - such as a boat yard for the
fiberglass repair and interior redo. But at this time of year they are also very busy and you will be paying a pretty penny to have them do it all for you. Once you get a new frame and
axle on it the outside repair and inside redo might be something to shop around the boat builders to see if any will do it over the winter months when they are often looking for work.