Well pardon my french but your an idiot if your doing a word search for bar, tube or cage and actually expect to find anything.
But since your unable to do the reading yourself I suppose I shell do it for you.
102 - “Regulations, safety devices” - designating devices and designating an organization to test and mark its approval of any device so designated, and prohibiting the incorporation or use in or on a vehicle of any device so designated that is not marked as approved by the testing organization."
So as I said, you can add a Roll Cage as long as its been approved by a designated organization such as the tech guys @ mosport.
Then, from there the MTO will make sure the Cage does not interfere with the driver via a basic safety. If they car passes then you can legally use the Cage on the road. Unless of course you are now going to argue that a Roll Cage does not fall into the category of being a “Safety Device” ?