Make 'em. Use a drill bit to determine the exact diameter of the hole and if that is a standard size plus a little for a tight fit go to a good hardware store and buy dowels. Use a band saw, or some such to cut bushings to the size needed. The point of bushing is to first help the block driller align the bit and to allow the bit to have a path to follow. Since these are larger holes you can carefully center punch the middle of the bushings for your guides. No need to drill them out. You can contact hardwood suppliers and get oak, maple, walnut and mahogany dowels for a more 'dressed' appearance. If these are (with CHickering very like) an odd size and if you have a friend with a machinists lathe they can be made easily and quickly with but one set up. Get over sized dowels, drill a hole in the center and then use a cutoff to cut to length. Nice hard maple would be very nice. Newton
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