Hi
a William Wallace married a Sarah Montgomery reg district Milford 1879, Williams father was Joseph Wallace, Sarah's father was George Montgomery
This marriage took place at Glenalla, COI Church, Rathmullan
A George Montgomery is recorded in Griffith 1857 living in the townland of Anny, Far & Near, Parish of Killygarvan
A William Wallace is recorded in the same records as living in the townland of Glenalla, Parish of Aughnish
This marriage does not seem to be included in the Family search site
Regards
Joe