Canadian Mathematicians

I hope the title to this post isn't too misleading. Let me explain myself.

Like so many other Canadian, it's hard for me to spend the extra $$$ on Canadian Canon lenses through Henrys, Camera Canada or Vistek.

I noticed the imported Canon 70-200mm f/4 L was available at B&H for $549.95 US. Now here is the math part of things: How much can I expect to pay for this lense if I order it? Is this the right equation?

($549.95 + S&H) * exchange rate * 1.15 = final lense cost.

1.15 being Ontario's provincial sales tax. Have I forgotten any fees such as brokerage or custom fees? They are offering me the following S&H services:

AIRMAIL PARCEL POST
7-10 Days Delivery $29.00

GLOBAL EXPRESS MAIL
2-3 Days Delivery $38.50

UPS EXPEDITED
2-4 Business Days Delivery $31.00

UPS EXPRESS
1-2 Business Days Delivery $38.00

FED EX ECONOMY
2-4 Business Days Delivery $59.00

FED EX PRIORITY
1-2 Business Days Delivery $73.00

Am I better off with one that another considering it has to get through customs?

Thanks for helping me out with this one. I might not have this lense for Christmas (they are out of stock), but with your help I might know if the price is right.

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