I don't know if you are still active on this site or if you will see this as I seen your email address is hidden.
I am also looking for Durack information and more specifically in the Cobden, and Renfrew County area.
I don't have much information at this time.Jack Joseph Durack born in Cobden abt 1936-1940.He fathered a child with June Laporte of the Renfrew Laportes.
I found 2 newspapers articles for Hudsons Hope British Columbia, outlining a Jack Joseph Durack who was from Cobden area, 24-28 yrs old who died as a result of trying to rescue a co-worker in the aftermath of an explosion in a tunnel, near Peace River.
Perhaps there is a connection to your Duracks.Would love to see if we could find a link!