I have information on two James Conaghans who came to NZ about the time you mention and both from Co Donegal. One married Catherine Rochford on 21 August 1888 in St Patricks Chuch Kumara South Island NZ. His parents were John and Bridget Conaghan farmers Co Donegal. They have descendents in Christchurch NZ. The other was from Castledooey Raphoe Co Donegal and lived 1839-1898. He married Mary Tanguey about 1881 unsure where they married or when he came to NZ. They lived at Balfour Southland NZ. Hope this is of use to you.