You may only import worked African elephant ivory for personal use as part of a household move or inheritance or as a musical instrument provided that the ivory was legally acquired before February 26, 1976; the ivory has not been transferred from one person to another person in pursuit of financial gain or profit after February 25, 2014; and the item is accompanied by a valid Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) pre-Convention certificate. Worked elephant ivory can also be imported as part of a sport-hunted trophy if all other requirements for sport-hunted trophies are met. Once the importer has obtained the US CITES Export Authorization from the US, you must then apply to the Canadian CITES for the certificate to import the piano at http://www.ec.gc.ca/CITES/default.asp?lang=En&n=05BFDC16-1
It is imperative that you obtain the authorization certificates prior to shipping the piano into Canada. If you attempt to import it without the necessary certifications, the piano may be seized at the border which will incur much difficulty and expenses to the importer.