Sounds like everyone got new tires at the same time.
Did they give you an idea when more would arrive at the shop?
With the season being so mild and winter not hardly shown up here in NY (other than some lake effect north of me), maybe a day trip to Niagara Falls to a Firestone Complete Autocare dealer. Being such a common tire size, maybe you could call ahead and see what they have them in stock, make a road trip out of it.
Does the exchange rate right now help or hurt you folks in Canada? I can't imagine you'd have to pay anything else more at the border if your driving on the new tires. Just make sure the blueish coating is off the tire before crossing should they be raise white letter tires.
I'm a big fan of these Revo2, and I think you'd be happy if you can wait. I've never had new set of tires improve a truck as much as they did. Keep us posted.