Yes, that would certainly appear to be a "Cadet Carbine" - which is a uniquely Canadian creature, by the way:
Canada's military forces (Militia) were among the first anywhere in the Empire to receive the "new" Snider-Enfield rifles (converted from the P'1853-family of .577 muzzle-loading Enfield rifles) in 1866-67, to enable them to better meet the Fenian Raids threat .... but were also among the last Empire military forces to still be using Snider-Enfields, long after they were hopelessly obsolete. Canada did acquire some .577-450 Martini-Henry rifles, but the great majority of those remained in stores and were never issued. When the bolt action .303 Magazine Lee-Metford was adopted by Britain in 1888, Canada purchased very few, and the venerable Snider remained our primary-issue military longarm. The Magazine Lee-Enfield rifle (with its improved rifling for cordite loads) was adopted by Britain in 1896.
At about that time Canada had finally decided to loosen the purse-strings enough to acquire a more effective military rifle to replace the nearly worthless Sniders - and made the brilliant decision to purchase 40,000 .303 Martini-Metford
single shot rifles! However, in view of the significant prospect of war at that time between the United Kingdom and the United States over the "Venezuela Crisis", Britain pressured Canada (and, I suspect, also offered financial inducements) to acquire the same number of the more expensive, but unquestionably more effective, new Magazine Lee-Enfield rifle.
However, it was years before all units of the Active Militia were finally equipped with repeating rifles - in fact, the last Snider-Enfields were not withdrawn from the Militia until 1907!
In the meantime, one use was found for at least some of the tens of thousands of 3-band .577 Snider-Enfield infantry rifles - they were cut down into approximately the same configuration as the Snider-Enfield cavalry carbine for issue to the many Cadet Corps in the country at that time. However, the original rear sight was retained and a simple bead-type foresight was installed on the shortened barrel with the result that, even though they were fully functional, if fired they would print excessively high. In fact, their primary purpose was for parade ground and marching drills, and each Cadet Corps was to be issued with two Lee-Enfield rifles for actual musketry instruction. As already pointed out, your carbine would certainly appear to be one of these cadet carbines. If you look at the front end of the forestock, you should be able to make out the wood plug filling in the clearing rod channel of the original full-length rifle.
Here is a comparison of a Snider-Enfield cavalry carbine (top) with a cadet carbine (bottom) -