The oak-leaf hangers are what inspired us to do the hall tree in the first place. They are cast iron and painted flat black. We bought them at a local building materials reuse place, which I am happy to promote. They have wide variety of stuff, prices are great, and they are very friendly.
For you Oregonians (or those visiting), here is the list of reuse and recycling centers. I try to build as much as I can from materials these centers provide. It's good for the environment, my wallet and the local economy.