Searching for family of Leslie Smith born in the 1770's - Randalstown area

My 3x great grandfather was Leslie Smith who married Frances Harbison/Harbinson - (possibly Harrison) about 1805. They were tithed in 1834 in Magheralane, Drummaul, Antrim. They had a family of 10 children including William, Robert, Frances, Margaret, Jane, Catherine, John, Leslie, one unknown son, and Elizabeth. I am not sure if William was the eldest or possibly Robert. These children all named their first female child - Elizabeth. I suspect that Leslie Smith, Sr. was born in the 1770's and Frances was about 10 years younger. In 1832 William Smith moved to Ontario with his new bride, Sarah McClenaghan; and it is possible that Robert relocated to Montreal about the same time where he became a merchant. The remainder of the family left Randalstown about 1840 and settled on a farm near Brockville, Ontario. In Ontario they were allied with a McCann family which could have been from Randalstown as well. Would anyone have knowledge of a Smith family using the unusual (for the time period) name of Leslie?    Laurie Simms, Denver, Colorado, USA