Welcome to Ireland Reaching Out!
I'm going to assume that your ancestors were Church of Ireland or Presbyterian. Records for the C of I church in Killteevoge start in 1818 and they are not on Roots Ireland. Maybe you could e-mail the C of I church closest to killteevoge parish in the Diocese of Raphoe (or maybe the diocese) to find out where the records are held. Here is the link to the C of I Parishes in the Raphoe Diocese. If George and Eleanor married 1845 or later there should be a civil record (if they were not RC).
Let me know if you have questions.