Hey Tannie... it depends on how many sbs you have and how many giftcards you are looking to get.
If all you have is enough sbs for 2 gcs, either amazon.com or amazon.ca.... then you probably should cancel the .com order and place a new order for 2 .ca ones. If you cancel and reorder, at least then you won't have to rely on finding someone who would trade.
If you have enough sbs for 4 gcs, 2 purchased yesterday and you want to place an order for an additional 2 today.... then I think you could leave the two amazon.com ones as is, hoping that eventually swagbucks will reply to your email and change them to .ca.... and you can purchase 2 .ca ones for today. That way hopefully if swagbucks helps you out you can get 4 gcs.

