Unless you ship parcels yourself regularly, it would be a surprise to learn how high postage costs can be.
For example, it costs me over $12 to ship a 2.5 cm thick paperback book from Ontario to Alberta. Higher if it weighs more than 500 grams.
Same goes for shipping from the USA to Canada.
Although the US to Canada question is confused by the Harper government's insistence on retaining a risible $20 maximum for duty-free imports (compared to the $200 allowance for cross-border shoppers), the cost of shipping by USPS is comparable to shipping within Canada.
You can guesstimate actual shipping costs within Canada here:
https://www.canadapost.ca/cpotools/apps/far/business/findARate?execution=e1s1
You can guesstimate shipping by USPS to Canada here:
http://ircalc.usps.com/
Don't forget that your purchase may attract duty and sales tax as well as a service fee for the shipper.
