Can I buy credit for Skype from a Telus store, in Montreal if possible?
While surfing the net I found this page: https://support.skype.com/en/faq/FA12323/how-can-i-pay-for-skype#c that, for Canada, indicates Telus as a modality to buy credit, for Skype, which can be used, for example, for sending SMS-es, directly from a PC, to mobile phones around the world.
Can I go to a Telus store and buy a prepaid Skype card?
The link on the Skype page you posted for Telus no longer exists. The methods listed on that page are not Skype cards but methods of payment for Skype. There was a deal between Telus and Skype way in the past (2011) but that likely no longer appears to exist.
It seemed to revolve around a Skype branded LG phone and the ability to buy Skype credits through your Telus account. That deal no longer appears to exist. Your best bet to buy Skype credit is still a credit card.