You may request maple leaf card at the time of landing. However, you may not get it right away. It takes weeks for processing. Also you may be requested to take picture for maple leaf card. If you landing via flight, the immigration officer is quite professional. Everything is quite smooth. If you drive up to landing, make sure the picture is taken properly. Otherwise, you may be requested to take second time after you land in. In this case, if you are in Canada, it's fine. If you are outside of Canada, you'll need to go back to Canada again. Since you need to go to their assigned studio to take picture.