Our Port of NYC has a number of Lines that offer sailings in the Fall to NE/CAN,
Our particular line is Cunard with the QM2. We visited Halifax, Boston, Sydney, Sept Iles, Sagnarney and we stayed in Quebec for three days on the ship.
Some also go to Bar Harbor, Cornerbrook, Portland to name a few.
Do you research. I know many we know like to do a day or two at the Departure Port to tour and then take the cruise.
Good Luck on your decision.