We were up there (Canada) in April and a long-time, long-haul trucker from Canada (at a pay phone) told us that the only way to go was to purchase a phone card and use that.  Wasn't the easiest way to go, but it worked ok.  He said the cheapest place to buy one was at 7-11 stores.  I think there is a cheaper one at Costco, though.  These days the pay phones are kind of disappearing and require a lot of looking when trying to find one.

  Bob & Sharon Mendonca
  88 Westy
  88 Vanagon GL