Actually, that's a common misconception. Indeed, in the modern era, the mountie
is just a typical police officer, however, when they were first introduced in the 1870s, they were, for all intents and purposes, a military regiment (essentially an 'occupational army' for the freshly-annexed North West Territories). Indeed, when the organization was first to be created by an act of parliament, many parliamentarians wanted to call it the 'North West Mounted Rifles.' The name was softened to 'Police' in order to assure relatively peaceful relations with the local natives, but its
raison d'etre remained the same.
Furthermore, the Mounties acted very much as military forces in the suppression of the North West Rebellion of 1885, and by the time of the Boer War, were probably the best trained forces in Canada, military or police. For that reason, an army of Mounties formed an imperial cavalry regiment in South Africa, led by no less august an individual than Sam Steele himself. Steele, of Klondike gold rush fame, was called out of retirement by Lord Strathcona, who was also known as Donald Smith, the one-time-conservative-turned liberal who drove the last spike into the Canadian Pacific railway.
Sorry about this long-winded, trivial and somewhat boring load of information. I've been reading too many Pierre Berton books recently.
Anyways, the Avro Arrow would be a poor choice for Canadian UU, as they never saw combat, and only five of them were ever actually produced (all of which were subsequently shredded and dumped to the bottom of Lake Erie because of American political pressure).