i decided i didnt want to wait for buku clutches to get back to me and went ahead and cut some steel shoes today.
they were actually quite a pain to make. the basic shape was easy, but having to jig them up one at a time to cut the large slot for the spring, then change to a smaller end mill and re jig them one by one to cut the small slot, and jig them in the drill press to drill the hole.
they ended up a little lighter than i figured at 3.7 grams, but thats because they are a little smaller in the arm than the aluminum shoes. im going to try them in the trailing position with some 1.0 springs and see what happens.