I like the Caldwell Jr. And the Caldwell bags. I have a plastic rest that works good, but its a pain to carry around.
When hunting I use a shooting stick. Although in one tree stand... anyone ever use a rope swing? Its a cord hung off a branch down to your foot. You push down to raise it and of course relax to lower it. The rifle rests in a loop. The purpose of this is to be a good steady front rest. Your shoulder is the back rest. It works a lot better then you think, and all it takes is a length of rope to set up, and a tree of course. But I have used that in times of tree sitting.