I had a solid fiberglass spinnaker pole used on a small sailboat delaminate badly. Size, strength, and flexibility are on the order of an English longbow. As the pole was out of manufacture, the local chandleries had no stock, and eBay didn't answer, I was in a bind.
What I did was rig up a jig to rotate it very slowly and wrap with 550 parachute cord under tension.
About every foot the cord is locked to itself with epoxy, I think 3M DP220 since it's reasonably flexible. Its worked for several seasons and I'm no longer extracting fiberglass from my hands.