Medical insurance for the Elderly (Vancouver)

Hello,
I wonder if anyone has any information or ideas about getting medical insurance for an elderly person who would like to move from London UK to live in Vancouver? Specifically, I am talking about my mother who is 91 and who would like to move here to live and spend the rest of her days with my sister who is married to a Canadian. I realize that the age factor is quite prohibitive because I have tried, and I think, exhausted just about every possibility. So this is a bit of a long shot - but if anyone has faced the same problem or has any ideas, then we would be very happy to hear from you. Thanks.