Hey Fellow Ontarian! Went to cuba last year and the number one rule is dont buy off the street, off the beach, or someone saying "cohiba cheapie cheapie". Go to a store were they are legit. Ask for "Casa de Habanos". Any cab driver or horse and buggy guy will know what you are talking about. Dont buy in the "malls", they are real but very expensive, go to a store within the city, either Havana or Varadero or Holgiun.
I recently bought a box of Punch Punch and it cost me roughly $180.00 Canadian.
Watch the exchange rate on the Cuban Convertible Peso, try to echange at the Airport.
Good luck, make sure these points are clear to your friend, because the last thing you want is him buying off the street because he thinks its a better deal.