I found your post difficult to the point of incomprehension.
There are abt 1,000 McCabe B and 418 M rcds in Co. Louth between 1700 and 1921. I think only RC rcds are in it.
Google "Irish Family History Foundation" to lead you to its database. There are 0 Mathildas or Matildas, but a few Elizabeths. It is easy to use except where an errant priest used abbreviations for forenames.