http://www.amazon.com/Seville-Classics-5-Shelf-14-Inch-Shelving/dp/B00CL9204C/ref=pd_sim_hg_10?ie=UTF8&refRID=1N0X84YW565KTB4F0HSJ
The bigger/wider you get, the price tends to shoot way up. Very cool idea though.
My guy likes to climb but I'm sure most will just chill on the horizontal branches. I'm hoping the background combined with my mistking will retain humidity well.
You can just apply the substrate straight to minimize the footprint reduction. I know they sell tree fern panels, but that might...
Here is a GSF background with Titebond II and cocofiber + organic peat. You can really get detailed with backgrounds but I had to finish this quick because I am moving. There's also planters stuck in the background. Adding the variety of plants is the funnest part of the project :D.
You can put Great Stuff Foam on the 3 faces of wood and then apply a substrate to it. It will make the cage look more naturalistic as well as water proof the wood.
I'm actually doing something similar with a screen cage :D. I've completed the background so I'll post a pick to give you an...