No person shall sell, or offer or expose for sale, any canvas or rubber footwear that has been imported from a foreign country without notifying each person purchasing or intending to purchase that footwear that it has been imported, by displaying in a conspicuous place, in letters at least as large as the figures indicating the price of the goods sold, a sign marked “Imported goods.” If the goods have an individual price marking, they shall also be marked with the words “Imported goods” or the country of origin.