Www.pcpartpicker.com
Top right hand corner, set country for Canada.
Scroll down, pick OS. That'll give a listing of OS's to choose from. Pick the one you want, click on it and it'll give a listing of local e-business that deal with Canada sales.
If you already have the Win7 ultimate key, and just want a CD, contact Microsoft directly, or just dl it directly from Microsoft and burn it to CD.