What you are looking for is a “Sail Track Stop” and you can get them at places like West Marine or Defender. The “Doohickeys” are called sail slugs and you prefeed them into mast slot and lock them in place with the sail track stop (you can do this at the dock). Then you can hoist at will from the cockpit. Especially on small boats, the mainsail folds more compactly on the boom if the slugs are let out of the slot at the end of your sail. A previous owner must have misplaced the stop as it is rather small. The C22’s originally didn’t have sail slugs but instead, you had to and feed the bolt rope up the slot. Needless to say, you had to do all of this from the mast. The sail slugs makes it more convenient.