Hi, Marriage Registration - will show the Place of birth of both parties. Available from Govt of Alberta Vital Statistics - there is a fee.
Obituaries for your grandparents - may mention their places of birth - names of other family members.
Death Registration /Genealogical Registration/Long Form Death Certificate - will show the place of birth, names of parents - as known by the informant.
National Registration of All Canadians over the age of 16 years. In the early 40's . This information is available - cost is $48.15 - returned if no information found *I believe that $5 is kept back.
Cheers, Stella