FWIW, if they do divert you to Nova Scotia. It is an amazing town. One of our favorite ports. We compare Halifax to Annapolis or Inner Harbor Baltimore MD. It is a great walking town with some very interesting history.
At the port that you come through there is a memorial. I can't recall the name of the ship. It was a history lesson I never knew. A ship with Jews during WWII arrived and Canada did not allow them to immigrate. They were sent back to Germany, and they have all the names of those that were sent back and died due to the Holocaust.
There is a great whiskey/scotch (not sure which) bar that is right across the street from where you will find the lobster roll trucks, and the docks for personal boats. For our DS that moves back home to baby sit the dogs, we always buy a bottle of specialty alcohol as a thank you gift to him.
The Titanic memorial is probably a 15 min walk from the ship.
As you walk from the ship to the Titanic and right in the thick of it, close to the food trucks, there is an amazing silver store on the left side. It is tiny. We always give our kids a christmas ornament for the tree. They had an amazing high quality unique ornaments at a good price. I also got a unique necklace there that people always compliment me on. It wasn't cheap, but it wasn't expensive either.
They have an indoor specialty food/soaps/etc market close to the port. I picked up unique soaps there. Memory is a little foggy, but across the street there is a micro brew that you can get a flight of beer at a good price, and great quality according to my hubby. I don't drink beer which is why I only can kind of remember its location.
Every place we ate, drank or shopped at took US dollars, but gave back the change in Canadian $. The indoor market was our last stop, so the change he got from buying his lobster roll from 1 truck and poutaine for me from another, plus the beer flight was where we paid in the Canadian $. We still had some money left, and my husband wanted to get a polar fleece at the market attached to the port. Probably paid too much, but oh well. He paid with the left over CAD and the rest on our credit card. Only saying this, so you can see that you don't need to convert money.