I tried the fabric stores in town. None had wool felt. I ended up cleaning the old felts in acetone and they came back to life. Let them dry, oiled, and put them back on the lathe.
Fly fishing boots have felt soles that you can buy. Here is just one link http://www.cabelas.com/p-0033917.shtml I have used a tight nit wool sweater for felt also. You could probably find one at a thrift store?