APA form for legal citations is based on The Bluebook: A Uniform System of Citation.
The examples in the APA Manual are all US cases. However, when you go to The Bluebook, you find that the format for Canadian cases is slightly different. See pages 298-303 of The Bluebook.
The examples in the Bluebook all have (Can) as the jurisdiction at the end of the case. It is not wrong to add, but not needed - as you are in Canada citing Canadian Cases.
The APA Publication Manual says: "References to legal materials...which include court decisions, statutes and other legislative materials, and various secondary sources, will be more useful to the reader if they provide the information in the conventional format of legal citations."( p. 216, para.1)