Supposedly Avis has cars with snow tires, though they always seem to be sold out whenever I want one.

http://www.avis.ca/car-rental/conten...s-CA_en-012015

There are also day bus trips from Banff to Kicking Horse that would be an option for you. They pick you up around 6:30am and you're back around 6:30pm, and the cost includes the bus and lift ticket.
http://www.banfftours.com/banff-acti...powder-express