What's your providers rate? I never use XE when calculating purchase cost as the amount varies.
St.George has the AUD at 0.8565 while Paypal has it at 0.8639
So that $155.90 now looks like $180.45AUD if you payed with PayPal or through the bank-ad the foreign exchange conversion fee of a few dollars from some.
Throw in the $179 that target has it listed for & potential sales % off & there really isnt all that much of a reason to buy online right now.