No, you cannot 'just buy' a 'presto card'.

Astonishingly, the 'change collectors', who only sell tokens don't sell Presto cards.

Yet another mind-blowing bit of incompetence.

In Montreal, not only can you buy temporary cards (with money or visa), but you can also put rides on them in a fully automated way.

I will admit that the situation in Toronto may be temporary, but it's still utterly ridiculous.