New Prius C member!

Hi All! I found this forum by fluke while doing research on the Toyota Prius C, prior to my decision to lease one. After driving a Mazda 3 Sport for 4 years, I knew I was in for a major adjustment in regards to speed, but as I get older I realize that speed isn't everything. Finally 2 weeks ago I pulled the trigger on a brand new Black Sand Pearl 2017 Prius C with the upgrade package (I live in Canada and I'm unsure how that translates into the numbers 1-4 in the US), I opted for the 2017 over the 2018 mainly because of the lease rate was lower for the older model year. Having driven the vehicle for the past two weeks, I can easily say it's a great car. It's even made driving fun, turning each outing into almost a video game like setting, trying to beat your high score in fuel efficiency, or I should say in Canada beating your low score. Last night I was even impressed with my extreme cold driving fuel efficiency, so far with my typical daily commute I average 4.9 L/100km, in the extreme cold (-15C plus windchill and starting from an extremely cold start) I achieved 6.1 L/100km. I probably could've done better but quite frankly heat becomes a necessity when it's that cold.

The next two things I need to get done is have my after market XM Radio installed in the car and get winter tires. The first being a luxury that can wait and the other being a necessity before winter gets any worse.

The question I have for this group deals predominantly with winter tire size and not brand or model and specifically for the 2017 Prius C Upgrade model (unsure if the models make a difference on tire size). The recommended tire size listed on the driver side door panel is P175/65R15. My question is whether larger sized tires can be installed and if so, what size?

I am aware that changing tire size may/will affect fuel efficiency, however, at the end of the day my car will still be more efficient than the average car on the road and I prefer safety and cost over fuel efficiency. Larger tires are actually cheaper than the recommended size, and I do know that most cars can drive on larger tires, I've seen most people mention different brands and models but very little discussion on size. If someone can help me out with this it would greatly be appreciated.

p.s. Sorry for the long first post