The Municipality of West Grey consists of the former townships of Bentinck, Glenelg, and Normanby, the Village of Neustadt, and the Town of Durham. West Grey is the largest Municipality in Grey County and borders Owen Sound, Ontario. Hope this helps to locate the area for you.
There are a lot of records of Johnston families in that area. The url below has historical information for families in Grey and Durham.http://greycountyhs.ca/links.html
Grant Harper is Stephen Harper's brother and the other brother is Robert. Stephen Joseph Harper b. 30 Apr 1959 in Etobicoke, Ontario is the oldest of the three boys.
If you need information for Stephen Harper's ancestors, please provide your email address and I will send you the information I have.