I bought my roll hoop ready bent as part of AshG first group buy, from memory it was about £40 for the bent tube and then I bought a length of CDS for the cross bar and another length for the diagonals.
One other little thougt, if you mount the plates at the bottom of the tube, you can make the bolts hidden but still get a spanner on the bolt from underneath. See photo 1 and 2 in this gallery
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