Knowing that she will be flying out, there is a candy store at the Calgary Airport once you get through security at which you can buy soap candies. It is at the far end of the domestic flights area and is the kind that is in the middle of the aisle, not along the sides.
You will likely be departing from a different part of the airport, but if you get through security early and feel like a walk, go for it.
I just googled it – Sweet Factory, concourse D.
At least they had soap candies last time I was there (aka floral gums). You may have to ask as they are often hidden somewhere not too obvious.
The only other places I have been able to find soap candies at in recent years are:
-Nutters in Salmon Arm (surprising, no?)
-Banff and Canmore Candy stores
-Sugar Mountain in Ottawa
Yours for more sweets,