When will you be out of warranty? Unless you are going out of warranty now, nobody knows--the price will naturally go down, and the Gigafactory should dramatically drop the cost as well.
lets do some quick math here. 60 battery warranty is 125k miles or about 201k km. So if you have 50k km left on that warranty that means you've driven 151k km (~94k miles)?! If so, then good on you for putting in that many miles/km on a 60 in 2ish years! Otherwise my guess is your confusing the 4yr 50k mile B-to-B warranty with the separate warranty on the battery and drive train which runs for 8yrs. 125K miles. You've probably got some time before you need to worry about it.
Definitely 125k/200k km, even in Canada: http://www.teslamotors.com/sites/default/files/blog_attachments/model_s_new_vehicle_limited_warranty_2.1.pdf