Re: Keel: a.k.a Water Bucket
I would first concentrate on finding the source of this water. Bilge is a big suspect, so is the cockpit drain. Make as many holes in the keel as seem needed, then put a garden hose first to your cockpit drain to see if water is coming out of the holes in the keel. then try to do the same with your bilge. Once you know where the water is coming from, eliminate the leak and patch up the holes in the keel. It is a small boat so it can't be that hard or complicated.
I would buy the cheapest resin for the filler work, like that automotive bondo stuff, thickened with some filler but not too much, so it goes down into the voids in the keel. Then do the outside of the keel with a good marine epoxy.
Be kind, for everyone you meet is fighting a hard battle.