One person I am positive has the set up for it and has made lots of them is Jacoby Cues. It appears they now make the Schuler Cues cue line, and the conical taper (sometimes called a "constant taper") has been one of the Schuler shaft taper options for decades and Jacoby is still doing that taper for them today so they do a lot of conical tapers in the Jacoby shop. You should be able to call Jacoby toll free at 800-461-6066 to get a quote on one with a uniloc joint and at 12.5 mm. Make sure you also tell them (or whoever you end up having make the shaft) what your joint diameter is, or at least who made your cue butt if you don't know it and don't have the calipers to accurately measure it, so Jacoby can build the joint end of the shaft to the correct diameter as well.
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