Records for Glenelg and western Inverness where our ancestors came from are rare or non-existent for the period before 1794. Keith Dewar's self-published, out of print booklet has speculations about the origins of the family. There is a digital version of the book available on the Family Search website.http://books.google.com/books/about/The_MacLoers_of_Galder_G...
One speculation is that the Deors moved from Dull in Perthshire (near the Menzies Castle) to Glenelg around the time of the building of the Bernera Barracks at Glenelg in the early 1720s. It was here that the family intermarried with the local McLeods and became MacLeors (and variations of that name). It was also here that the name Roderick came into the family for the first time. There don't seem to be any Roderick Deors from Perthshire before this.
The oldest Parish Death Records I have seen for Glenelg list the names (but not the dates) of the parents of the early MacLeors and by doing the generational math it is possible to get back to the mid 1700s, but not as far back as the 1720s when they supposedly came from Dull.
I have corresponded with Alasdair McRae who lives in Scotland and who inherited Keith Dewar's research notes and documnets and so far there doesn't seem to be any definitive piece of paper that ties this all together. But we're still looking. Perhaps a pair of PEI eyes would help in the search!?http://peersuptonsmithdodd.wordpress.com
Some of my blog postings are about my Scots ancestors