What the hell did people do before oranges and lemons were consistently available in cold climates?

They... didn't eat them? Or at least, only very rarely, as special treats. There's a reason getting an orange in your stocking at Christmas used to be a big deal.

Check out markets for locally-grown produce. I used to shop at a farmer's market in Toronto that was great, but I don't know where comparable places are in Montreal. Jean-Talon, I guess, though I've never actually gone there. The one I went to in Toronto was just one day a week, a much less formal sort of thing, just set up in and around a community centre.