McCarthy/Sullivan marriage in Tuosist Parish

My late uncle, William McCarthy, did extensive research before he died; but sadly, most of it was not saved.  His daughter did come across some hand written notes that stated that our g-g-grandparents, Patrick McCarthy and Julia Sullivan, were married in 1844.  Years of searching the usual on line records have not been able to confirm this.  As far as I know, he never made the trip to Ireland to research other records in person.  So I'm wondering if there are obscure sources that he could have researched, or possibly he was in touch with someone locally.   He died in 2012, so the chances of finding that person are slim.  There ARE records of five children born to them while they lived in the townland of Derreenatlooig in Tuosist Parish between 1846 and 1852, before they emigrated in 1857.  I assume that Patrick was from there, as there is a Patrick listed in Griffith's Valuation in 1843.  (There were McCarthys and Sullivans there, as well as "next door" in Kilmakilloge ).   So, focusing on the marriage, does anyone know of other sources of information I may have missed?    (Note: the reliability of Wm's notes is bolstered somewhat by his other notes, including that Patrick had an unknown sister marry an unknown Hennessey, and moved to the U.S.  In 1890, Patrick's brother willed land to his nephew, Thomas Hennessey )   I have taken Ancestry dna and Y-dna with FTDNA.   GEDmatch AZ3369886     TIA.