John, my whole canyon is a rockpile. I cannot do anything in there without moving big rocks- as a matter of fact, there is exponentially more boulders than there is cobbles. But guess what is under boulders that no one else has been under? Answer: More big boulders.... I am getting really good at moving big boulders.
I just went to the local army surplus store and bought it. It was a few years ago, so I don't remember how much I paid, but whatever it was, it was a bargain as that stuff is bombproof. Most durable stuff I have ever used, and it isn't hard on your hands.