Skype can be installed on as many computers as you like.
Your user-name and log in are specific to you NOT the computer.
It doesn't matter who you are calling or where they are - it's you sitting in front of which-ever computer you happen to be sitting in front of at the time that is using your user-name and password.
The important thing is that you must not be logged in of more than one computer at a time. So make sure that when you go to the country that your Montreal computer is OFF