Ever wondered what that wooden thingy is on top of a rolling nerd’s kayak? It’s a throwing stick used since the stone age to throw sticks, like harpoons, further. A Norsaq. This is my first home made one. It probably took more than an hour to make, but not by much 
The motto is: Be practical, don’t overdo it. I kept a little bark on the piece of fir for authenticity.
If you want to use it as a harpoon throwing helper, your hand needs to grip around the norsaq and steady the harpoon so the width is dependant on your hand size. The more it looks like a paddle blade, the more water purchase you get for rolling. I heard the max competition size is 10x50cm. Good luck throwing a harpoon with that! However, it’s good for practice.
The Norsaq is a little harder to roll with than a paddle, but a little easier than a hand roll. If you fail, you get good practise at grabbing your paddle under water and roll up, like you would if you lose your paddle and have a reserve on board. If you’re learning hand rolls, the Norsaq is quicker to get hold of than the paddle.