I search the IFHF's online database @ ROOTSIRELAND.IE. It has abt 19 million B/M/D and other records for MOST Irish counties. Records before 1863 are increasingly sparse and almost non-existant before 1800.
For a marriage of the pair, anywhere in Ireland, at any date, I found NO records.
Less than 1% of 18th century records survived. There is a miniscule chance than more records from this era will be found and added to the database. Suggest you visit the database, register (free), and opt to be notified as records are added.