A new grommet is added at the rear of the sail for the outhaul line that runs back through a fairlead, and then forward to a jam cleat. This actually holds the boom on the gooseneck, as well as tensioning the sail. These sails are available cheaply due to a boom in windsurfing ten to twenty years ago. The one I use is pretty well shot, and I'm looking for a replacement. The boom is steel-wooled and lacquered so the sail and sailor don't get black smudges from oxidation.
Pop rivets attach the blocks and cleats for the mainsheet and outhaul.
Unlike a sailboat, stainless steel fittings aren't a great advantage. Blocks New blocks aren't cheap, so used ones are worth searching for at marine swap meets or even making them from scratch. The cheaper ones have plain bushings as opposed to Delrin ball-bearings but if they are used where the line has the least movement, toward the rear of the boom, they are fine. I like having a least one good quality block where the sheet exits the boom to my hand. I'm experimenting with a ratcheting block to take some of the strain off my hands during longer sailing sessions.