choose a post office at university of Guelph
charges sometimes higher than the other offices: I asked to send a registered package and was told no such service here, and then I am adviced to use xpress with a doubled charge. But finally I found out the shipment time is just same as the register mail (took 6 days to arrive at the destinaton in BC). Later on I found that another post office near the nofrill supermarket is providing register mail service with a half price and similar shipment time.