I didn't realise they were that cheap when new. I don't remember them being that cheap when I got them.
Costco has them at $147.99/tire, and KalTire will pricematch and beat by 5%.
$147.99 * 0.95 = $140.59 = $562.36 total
$23.00/tire installation (a ripoff, but whatever) = $92.00 total
Subtotal = $654.36
HST = $85.07
Total = $739.43
Less $70 online rebate = $669.43
Remember that rims, new, would be ~$70.00-80.00 each, so tack on another $316.40 to $361.60 (taxes in) for rims.