Best way to get to my ancestral home

I will be in Co. Mayo, staying 3 nights in Westport from May 7-10 this year.  My husband and I are in our 70's and will not have a rental car - we are using trains and buses during our 2 1/2 week Ireland visit, combined with organized day tours in our base cities.

My ancestors in Mayo are the Murphys (Castlebar) and the Cooneys and Carrols (Laghtmacdurkan).  I understand from some distant cousins who have visited that the remains of the old Cooney homestead are still standing in Laghtmacdurkan and it is very important to me that I visit them. 

Patrick H. Murphy, born abt. 1848 in Co. Mayo, was my g-grandfather.  His father was also a Patrick Murphy, b. 1812 in Castlebar, and HIS father was a Thomas Murphy. 

Margaret Cooney Murphy, b. 1825, married Patrick Murphy in 1843 in Meelick Parish, and she was my g-g-grandmother.  Her mother was Mary Carrol Cooney, b. 1794 and married to Patrick Cooney.

With the exception of Patrick Cooney, all of these people, along with the "Cooney boys", emigrated to the U.S. in the early 1850's and settled in Michigan City, Indiana. 

I'd love to see the area they were from.  However, without a car, I'm having difficulty figuring out how to make this happen.  I'm thinking that if we take the morning bus from Westport to Swinford, that we could possibly then hire a taxi to take us there.  But I have no idea if this is possible.  I'm also thinking that we could hire a taxi from Westport, but the cost looks extremely high.

I'd so appreciate any information from those of you in the area as to the best way to make this this happen.

Thank you so much for any help you can give me.

Joyce Casey Hagan