In Document Settings > Journal Entry, allow unbalanced foreign currency transactions long enough to complete the transaction.
Important: It is preferred to block unbalanced foreign currency transactions. If you choose this option, only allow them for a minute.
Put the money into the Clearing Account – ensure the net effect is zero in Canadian dollars.
Do an internal reconciliation on the Clearing Account.
Additional costs, like fixed fees in addition to exchange rate costs, could be added to the Journal Entry or reconciled at bank statement time.