Charlotte Anna Colquhoon/Cahoon

I am searching for themarriage record of Charlotte Anna Colquhoun. Most records I have her surname is Cahoon,except for her husband Francis O'Callahagan's britishmillitary recordwhere it states her maiden name as Colquhoun. Married 14 August 1907 Lisburn outside Belfast. My goal is to ideally tolocate the Parish that her parents had her baptised in and hopefully find her siblings records also. The 1901 and 1911 Irish Census states that the family are Roman Catholic, occupation of the head of the household is farmer. The address of the family farm land is 34 Creenagh Magheramesk Massereene Upper South Antrim. There are so many churchs in the area they may possobly have attended a couple of different ones. I have uploaded one sheet of the Millitary record of her husband Francis Callhagan.with the her correctmaiden name. I am not sure why these changes to surnames appear in their records. One therory is that the transcriber at the time wrote down what they thought they heard when the person was giving them information,I because the couldn't understand the heavy Irish accent. Would appreciate any info on local churches around this area or a web site where I could access parish records for this area