We’ve had a McMaster Carr account since 2007. This must have been before their policy not to accept new Canadian customers. Their customer service is second to none. My advice would be to email them explaining your situation(being a highschool team, exposing future engineers to their company, blah, blah, blah), and ask them to open an account for you.
Either that or find a local company that already has an account and doesn’t mind sliding a few parts in with their orders.
We are going to test them soon though.