RBF has pointed you in the right direction and as you will see from the website, the appropriate abbreviation, akin to OS map, is NTS map.
Concerning mapping in Canada and the size of the country, I remember a talk by a Geological Survey of Canada staff member, when I was a student at a UK university. He pointed out that if the GSC started mapping Canada at the same scale as the BGS in the UK, it would take over two hundred years!