The stamp has to be accepted where you mail the letter. If you are mailing in Canada, you need a Canadian stamp. If you are in the US mailing to Canada, you can use a US stamp.
Canada
Yes, Canadian border officials typically stamp passports upon entry into Canada.
You use the postage of the country of origin, in this case, you would use Canadian postage.
To obtain a Canadian passport stamp, you must have a valid Canadian passport and enter or exit Canada through a designated port of entry. The stamp serves as a record of your entry or exit from the country.
A Canada two-penny black is an old, Canadian postage stamp.
what is the cost of a first class satamp from us to canada
4 cents
0.57 cents in 2011
Canadian stamps are only used in Canada. When mailing a letter, you use the stamps of the country of origin. So only Canadian stamps can be used there.
32 cents
50,000 canadian euros