I think you are the gentleman from Newfoundland, Canada. If I am wrong it changes things.
I do not think finding the tank is the problem but current shipping costs may be. First check with your local garages. If things have not changed there is a used and new gas tank distributor set up somewhere over there unless they have withdrawn from the island. The local garages should have a number for them.
There are also probably some 114 parts cars around the halifax area so that one might be located. If you still travel to new york regularily that would simplify it as well. I originally missed that you had a 114. The post following mine corrected me as I automatically thought 123. Unfortunatly I do have a spare 114 gas tank but need it as well.