I don't think you want lazy jacks but you probably want a topping lift. A topping lift holds the boom up when you drop the sail. Usually you slack off the topping lift once the sail is up to keep it from interfering with the shape of the sail. In my catboat (monohull) the topping lift runs from the **** to a cheek block at the bottom of the mast, up the mast to cheek block a few feet below the top of the mast. It then fastens to the boom a few feet in from the end. It is cleated in the ****. I would expect you would have the sail furled and have a couple of ties holding it (the ties are called gaskets).

I have seen people raise an H-16 sail and tie it off on the cleat without hooking it (mostly by mistake) and it worked. Can you beach the boat at the end of the canal before you start sailing? If so, that would make it easy to hook the sail before going out.

Howard