Bought 3 cans of 300ml mother for $1 each from 7eleven balaclava (Cnr. Carlisle & Hotham Streets).
The store guy told me that those $1 drinks containing 300ml mother, 500ml monster, Golburn Valley Flavoured Milk and Berocca drink are used for clearing their stocks.
They advertise those $1 deal out of the store door.
So just ask your nearest 7eleven store, they might have the same deal.
Confirmed in Frankston too. Saw it yesterday.
It's not the $1 deal, they're just clearing stock out. The guy told me it won't be back for another 3 months or so.