Hi, if your grandmother married a Dowell, then her parents were Archibald McQuarrie & Mary Hitchens who were married 8 Nov 1873. Archibald was about 24 years of age when he married and was the son of "Archie & Sarah" McQuarrie. Mary was 19 yrs and her parents were James E & Abigail Hitchens. Witnesses to the marriage were JE Hitchens and Lauchlin McQuarrie (Mary's father and Archibald's brother?)
At the time of marriage, Archibald's occupation was listed as a bookkeeper, however, Mary's father was a merchant -- so Archibald likely took over the store at one point.
Hope this is helpful!!