Non FJ Related - Cheapest Phone SIM for Canada/USA

[Sparky84]

Hi Guys

My Daughters going to Canada (mostly) and USA for a month and last time she went to Europe for a month she paid $200 for phone usage, mainly Data will be needed.
Looking at local Auspost travel SIM cost for 1MB is $1 in Canada and 0.25c in USA, I know she tries to use free WiFi where she can but sometimes she can't.
Is there any cheap phone SIM she can get when she arrives in NY which would work in Both countries, from looking most seem to work in one or the other but not both.

Thanks in Advance

Cheers Alan