Hey r/australia, I was wondering if anyone could help me out with tracking down an out of print book?

My parents are undertaking the Heysen Trail which is a walking trail in South Australia. The Department for Environment and Water (actually DEWNR before the name change) used to publish two guidebooks for the hike which were really good, but stopped in 2014 to switch to a series of eight pamphlets.

My parents have a copy of the southern guidebook (Cape Jervis to Spalding) but were disappointed to find that the books are now out of print. I'm trying to hunt down a copy of the northern guidebook (Spalding to Parachilna Gorge) for them to complete the set. I've searched google and ebay and bookstores but come up short, so I thought I'd try put the word out here!

If anyone had a line on one or was willing to part with theirs that would be incredible.