Hi there,
While it’s nearly impossible to offer an exact estimation based on a digital image, I can tell you it’s from the 1897-98 Queen Victoria ‘Maple Leaf’ issue—specifically Scott #66. The regular issue is listed in the Unitrade Specialized Catalogue of Canadian Stamps as $6-$12 used and $2-$20 mint (plus 200% for a never-hinged example).
Is this image the actual example in your collection?
Happy collecting!