Last summer, knowing that the local Provincial Police detachment was about to begin visiting many of the smaller 'cottage country' lakes in my area of Haliburton, I wanted to make sure that both my canoes and small tin boat with outboard were effectively 'legal' if a patrol happened by. I went to the local Home Hardware store where I found an inexpensive, purpose-made 'kit'. It was a plastic Tupper-ware like container (with lid), which could qualify as a bailer. Inside were a 50' floating neoprene rope; a whistle; a small, waterproof flash light. The whole thing was wrapped in a waterproof film. I tossed one in each craft, unopened. In fact, I even got a third and tied it to the mast of my sailing dinghy. Now, any of my craft that leave the dock do so "equipped". These things don't take up a lot of space, meet the legal requirements and were not very expensive. I seem to recall they were about $15 or so. I wouldn't be surprised if they could be bought on sale over the winter months.
One thing I found, though, was that it's impossible to toss a piece of neoprene line more than a few feet. It's like trying to push a piece of string. Solution: buy a small, toy rubber ball like dogs chase and young kids play with. Punch a hole through it; push one end of the line through and tie a knot or two. If trouble does occur, and if a young child needs to throw that line in an emergency, just having that little rubber ball on the end makes it easier for everyone.