I searched the Irish Family History Foundation's database. It contains 12,000,000 surviving rcds for abt 65% of Irish counties. Rcds are increasingly sparse B4 1840, rare B4 1800.
For Francis McParland (+variants) B ???? in Armagh, I found 43 B rcds.
For Sara(h) Lynch ditto, I found 13 B rcds.
For Sus(xxx) McParland ditto, I found 10 B rcds. These range from 1821 to 1894.
For a Sarah and Francis marriage ????, I found potential matches for the two in 1836, 1857, and 1867. Will let you screen these to see if you can find a match at the parish level. Matching M rcds will help you find a B date(s) for Susan.
Google the Foundation's name to lead you to this database. Register, opt to be notified as rcds are added and browse. Pls post your search results to my genforum msg.