I am in the US and have had many swaps over the years with New Zealand and Australia and never had issues with either. It does seem to take a while since its pretty far away normally 2-3 weeks. I know that Canada has very reliable post but does tend to take a bit longer than here in the US so I would imagine you would be fine but maybe expect to add another week on top of how long it will take. Hope this is helpful.
No issues sending between Toronto and AUS/NZ. I’ve swapped several times with both. More likely it takes more time for our Canadian letters to get over there than the other way round
