Modbargains, with holloween discount and free shipping.
ModBargains doesn't take Canadian forms of payment. I was going to order a ton of stuff through them to go full Cobb Stage 3 but they don't take any form of payment from Canada other than a direct wire transfer which is beyond inconvenient.
As for OP.
I bought mine used on the "other" ST forum for a dirt cheap steal. I think that's your best bet is to buy one used. All the Canadian suppliers want north of $600 CAD and obviously plus taxes. But if you want to spend that check out JRP in Mississauga or Allcore performance in Scarborough.
Most small parts shops also get great deals on alot of aftermarket stuff. You'd be surprised if you just call around a few parts stores if they can get Cobb.