I think that boler
will be quite simple to fix, don't confuse easy with simple.
4-maybe 500$ Cdn plus talent and time.
Strip the interior push the roof up into place and support it with whatever it takes to get it back in position, grind off the gel coat and some of the glass at the break lines.
Apply a layer or 2 of glas to the exterior so will maintain shape then go inside grind away some material at the breaks and apply a couple new coats of glas,
Once the body is rigid again sand and paint
, interior refinish will depend on what was there and condition.
It's a lot of work but fixable.
I did a job similar to this on a smaller scale to a truck cap I bought used that didn't fit right. I just cut the front off placed it where I wanted it and glassed in the space. The second pic is glass and body filler applied, third is after it was in service for several years.