Obviously your biggest problem is how much space you have available and the lack of an SD card slot, but your best approach is to check what meta codes are already released and then of those, see if the relevant map will suit.
The 990 meta codes are
hereThe Map Compatibility Chart tutorial is
hereOnce you've had a chance to read through the information you'll find that the one you want is Canada_Alaska_990_8365 that can be downloaded from one of the links available
here