The earlier the rcds, the more slip-shod the priests were in recording details such as parents' names. This appears to be the case for your pair.
You are left with two options neither of which are very good. The first is to look for their birth rcds using rules of thumb. The rules are females generally married at 21 +/- 4 yrs and males at 24 +/- 4 yrs. The second is to guess at the parents' names using the Irish Naming Tradition.
However, you are searching at the very edge of Irish genealogy history. Earlier B/M events either weren't rcd'd or didn't survive. You may indeed be at the final brick wall.