To be honest I wouldnt put 100% trust in Manx Orthography of that period - if you cant tie these pair into a Scots background then they may well be Killeys ! - have you checked burial records (if appropriate ?) - 1715+ was however the year in which Jacobite sympathisers decided Scotland might be too hot! - although the Island authorities claim there was no Jacobite sympthy on the Island (the tenor of their claim indicating that there was!) evidence is now emerging that there was significant sympathy - maybe these were comeovers due to that cause.