Forum member hushed informs us that the sold out 71021 LEGO Collectable Series 18 Party Minifigures is currently available for sale at Costco Canada online. They are sold in a box of 60 at $159.99. That means each minifigure works out to be $2.67 each (reg.$3.99). Savings work out to be 33% off.
Note that the regular minifigure retail price for both Canadian and American is priced at $3.99 each. This is a limited edition Series 18 LEGO Minifigures. There are 17 minifigures in each set.