From the Air Canada site:
Buy miles today for future rewards!
Use the bonus miles to help you take off when you're ready.
Coming soon: from May 7‑13 2020, you'll enjoy significant bonuses for all miles purchased (pics: up to 115% bonus).
Check back here starting Thursday, May 7 at 10:00 a.m. EDT
Travel at Home to accelerate your status
Reach Air Canada Altitude status without leaving the ground.
As an Altitude member, when you register for Travel at Home, 50% of the Aeroplan Miles you purchase (including any bonus miles earned) will count towards helping you get to the next Air Canada Altitude status or reach Altitude Prestige 25K.
Aeroplan is the frequent flyer program by Air Canada; as a Star Alliance members, this gives those with Aeroplan Miles to redeem flights on all the Star Alliance partners such as Singapore Airlines, Lufthansa, Thai Airways, EVA, and many more (there are 28 partner airlines in total!).
Since we’re not in Canada, the good people at Aeroplan won’t charge us sales tax either (a further saving) (flighthacks tested this).
Aeroplan at $0.014CAD per mile (sales tax excluded): 10 million miles up for sale with a bonus of 115%
Aeroplan at $0.016CAD per mile (sales tax excluded): 10 million miles up for sale with a bonus of 90%
Aeroplan at $0.018CAD per mile (sales tax excluded): 10 million miles up for sale with a bonus of 65%
At the time of writing, $0.014CAD is $0.015AUD
waiting for OzB'ers input……………………….