Sadly Air Canada seems to frequently overprice PE compared to a lot of their competition and I can never make heads or tails of their pricing. Sometimes it is reasonable, just above or even occasionally below Flex fares, other times they are looking for a $1000+ premium over regular economy ... and this is not just when there it is PE lowest versus flexible either, I am talking about just looking at PE lowest fares.

I would set some alerts with Google Flights or another tool and see if you can snag seats at a decent price. I have a trip to Brazil coming up and when prices came down I managed to grab PE both ways for maybe $200 premium over Y.