Below is where I got all the pieces for this zipline project.
Petzl Tandem Speed Pulley is available here: http://www.karstsports.com/petp21spet...

1" diameter x 18" long turnbuckle with jaws on each end (I actually used 3/4 x 24" but I said 18" in the video):
https://www.e-rigging.com/three-quart...

Galvanized wire rope or steel cable here:
https://www.e-rigging.com/three-thirt...

Carabiners:
https://www.karstsports.com/carabiner...

How to choose a climbing harness:
   • Buying a Climbing Harness: What You N...  
https://www.rei.com/learn/expert-advi...