Well, the briefcase with the 'bomb' in it (general consensus is that the bomb was fake).
The rig he jumped (Navy NB-6 or NB-8 Harness/Container with it's canopy).
The 'Training Dummy' reserve, container & butchered canopy.
The money bag from the bank.
The lines that were cut from the other reserve.
Of course, the body of a guy in a business suit (no tie) and the rest of the money. However, the above stuff is mostly synthetic materials (nylon for the most part). If Cooper died and wasn't found, there would be very little of him or the money left by now.
Mr Blevins - Good luck with your trip. It sounds like fun. I wish I could join you folks, but it's not possible.