This could be a DIY job if you are up to the challenge. The beauty of fiberglass is that if you make a mistake you grind it away & start again. It is not a huge mystery though many are afraid of it.
I have done many small repairs on boats plus a few to the 5er ranging from little dings all the way to constructing a new top for the boat, a new swim platform & re decking a small boat.
For this job I am thinking take the part off for starters & layer up a few layers of heavy structural cloth to provide structural strength behind to start with. From there work on the outside layering a few layers of fine cloth finishing with fairing putty. It is all about the preparation before the first coat of paint goes on.