Barnards in Oxton road is the only one I can think off that may have something like this in.
BODGE method - replace the "nut" with wooden dowel then use an ordinary wood-screws instead of the bolts. I'm assuming the nut is cylindrical, if not then make a bit of wood to fit. As long as you pre-drill with the correct size pilot hole, the dowel is amazingly strong fastening.
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