^^ i have not idea what Country or State would have the most trade with the Province either.
Here's an idea, why doesn't a home grown Newfondland airline take the risk & add a flight to Dublin if there's such a huge connection between the two places, don't even wait for a Western Canadian based airline to offer the service.
It might mean that every st.John man, woman and child has to make at least one trip a year to Ireland to make it profitable over the long run for an airline... I doubt that there is much demand for the Irish to travel the opposite direction and fly to the province...
If a country with ~100,000 less people like Iceland can make it work than Newfoudland shoudl be able to too.