I couldn't find one for one of my Cinelli stems, either. I took a Dremel tool and carefully cut the stem in the same shape as needed for the wedge type. It works fine. Then I couldn't get the wedge to work on my Ti stem bolt, wrong threads, so I re-threaded the wedge bolt. I'm sure I'd have been farther ahead just buying a beat-up used stem, but where's the fun in that?