Just in case it helps anyone to know the gaelic form of the name here is an excerpt from "In Famed Breadalbane" by Wm Gillies - chapter on Breadalbane surnames
STALKER. G. Mac-a'-stalcair. 1565, James, Ardeonaig; 1621, Finlay Dow, Crannich; 1638, John Dow, Crannich; 1644, John Dow, Kindrochit; 1763, Finlay, Keprannich.
James Mclnstalker, known as An Stalcair Bioch (The Brindled Stalker), was an agent of Colin Campbell, sixth laird of Glenorchy. He murdered Gregor MacGregor, son of James MacGregor, Dean of Lismore, in 1565. Soon afterwards he himself was slain by Gregor MacGregor of Glenstrae, at Ardeonaig.