Rudder repair/reinforcement

Had an unfortunate collision w/ a submerged rock and my roughwater weedless epic rudder (somewhat mitigated by the weedguard that sheared off first). Rudder is functioning but gnawed off a bit around the edges (up to 5-6mm).
What should I repair it with to keep it from weakening more?

If there's not much "mass" gone, you might be able to get some two part resin at the marine store, mix in a bit of those tiny glass filler beads to thicken the mix, and glop it on there, filling in the gaps. After it dries, you can sand it smooth. Or, there's another epoxy paste called PC-11 which is easy to find. Mix the two clay like parts together and put it on the rudder, then sand smooth after it dries.

I had the same thing happen hitting a rock. the end of the rudder splayed out on two sides. I used epoxy, and sandwiched the rudder in aluminum foil / high density foam / plywood in a vice so it got squeezed back together under pressure. Came out like new.