I'm not sure of the prices of components in Canada compared to the UK - e.g. US components are cheaper than UK components in comparison. Regardless, with that budget you'll be looking at a fairly budget build.
I'd probably go for an FX-6300 cpu with a GTX 950 but that's already $350 gone. However, if you go cheap on the board like many people will do (although some people will advise against although I've never had a problem with it) so something like a Gigabyte 970-UD3P board which is $115. Now at $465. EVGA 500W PSU for $50 now $515. A stick of Corsair Vengeance 8GB for $50 and a 1TB HDD for $60. So if you don't want a case you can build a pretty killer pc for $640 ish with a case make that $700. These are all amazon prices so if you shop around you may be able to get cheaper - but you could also save some money on buying a smaller HDD and a slower CPU/GPU. If you wanted to save money you could go $50 cheaper and get a r7 370 GPU which is only slightly slower than the 950.
Just a quick list of components that you could go for. Probably not the best but hey, it's what I could come up with in 10 mins. Maybe I helped, maybe not. Have fun. - Bungo