If the seller does not ship to Canada, then you cannot force them to do so. Many do not. If he ships to Canada, it will be in the listing. If you cannot get an accurate shipping rate in the listing, or if it says it only ships to the US, then don't buy it or bid on it. There is nothing else you can do.
Rick
"Egotism is the anesthetic that dulls the pain of stupidity" - Frank Leahy