All she will be doing with this laptop is internet surfing.
First, if all she is truly going to be doing is internet surfing (no email or limited email) then you may want to try a tablet. Amazon has a 9" Kindle Fire HD
for $300. That's the wifi version (the 4G version is $500). I bought my mother a the 7" Kindle Fire and she uses that thing constantly - it's perfect for one person and easy to use. I only suggested the larger one because it might be easier to view web pages with it (web pages are pretty cumbersome on the 7").
I noticed you referenced a Canadian webpage and I should tell you I'm referring to US companies. I think there would be a sister company up in Canada, but the prices and specifics may vary.
If you think a laptop would be better, then here's an ASUS i5 15.6"
laptop that's within the budget. You might find a cheaper one, but the cheaper you go the slower the laptop will be.
Bang for buck, ASUS is your best bet - and they make some pretty good and reliable machines. Personally, I've always had good luck with HP (my family has had at least 5 laptops) but I know many people have not.
Hope this helps.