Montreal Expos would be a very difficult find as it is no longer in existence & hasn't been for some time.
I live in Northern Ontario with no real chance of getting NHL or MLB fabrics but people who live in Southern Ontario near larger centres would be able to help you. There are huge fabric stores in Southern Ontario that carry sports fabric. The only one I can think of at the moment is Len's Mills but I do know there are others. Any Canadians out there on QB that can help this member?