Sorry Charlie, haven't been through the Catholic Church registers for St.Nicholas West - may have some bits & pieces, or info from searches of all County Galway - that's all. You should find quite a few Feeneys there & also in Parish of Rahoon which adjoins to the west. Catholic registers for both go back to early 1800s & Galway West Family History Soc has these in their database. They have a web page, & will search for the whole family for you in one go.
I was wondering about Castlegar in your subject title. I presume you mean the Castlegar on the north side of Galway, as St.Nicholas is also in Galway. I have been through some of the Catholic registers for Parish of Castlegar, noting all Feeneys I could find. I haven't yet put my searches into a computer database, so l'd appreciate a time period to search, & any info you have about approx. dates (birth, marriage, leaving Ireland, wives names). May be better to contact me direct at email@example.com (that's numeral one).
In any event, I'd love to include names, dates, & places info in my database to go into the computer soon. That way I can put descendants of Feeneys in same district in County Galway in touch with each other.