Portglenone, Tamlaght O'Crilly

My grandfather, Henry Molloy (1811 aprox -1882and wife, Isabella McKay (McCoy, McCew or similar)(1833? to , belonged to Grennlough Roman Catholic church. He from Derry an she from Antrim.

Their children wer baptized in the church. I'd like to find a record of their marriage. Could be around 1855.

Children include Anna (1860-1926), Mary (1862-1938), Rose (1863 to 1933), my grandfather, Patrick 1864-1936), John (1867-1941), Isabella (1868-1930) and Henry (1872-1948).  All the children, except Henry, the youngest, moved to the US. I'd like to determine when the parents, Henry and Isabella, were married.  I'd also appreciate any information regarding the family.  

They lived in Northern Ireland on a farm and Henry is shown in Griffiths.  It is possible that two or three of the children might have been married in the parish.

Thanks