Has it clogged because it went with an absent or empty ink cart for a prolonged time? If so, you might dare to try quite warm water next. I have once revived such a print head by putting it into a bowl of rather hot water, just deep enough to cover the ink inlets as well. Use that as an absolute last resort, and make sure you rinse, shake out and dry the head reasonably well before putting it back into the printer. This might make things worse - you have been warned.
Besides, tried the "intensive cleaning" cycle from the printer's control application yet?
Failing that, Canon print heads can be bought as spare parts, and most of them actually cost less than a new printer. When quoted a price, please mind they come with a full set of inks.