I recommend replacing the cleats, which is easy. However, jib cleats can be disassembled and repaired if you really want to. Typically the springs for the jaws break or pop out of place but if your cleats are 1980 original (Seaway?), finding springs may be a problem. This is discussed in another recent thread.

Replace your cleats with Harken H-150 (or Ronstan equal) with an eyestrap. These cleats are generic so you do not need to go to a Hobie dealer. Murray's, this Catsailor site store, West Marine, etc. stock Harken, about $30 each.

Your closest Hobie dealer is Backyard Boats in Alexandria. I have not had any need to deal with them (since Chick's Beach closed) so I cannot comment on service, parts availability, etc. Almost everything is available online these days.