Michael, talk to Peter Boulanger of Tesseract. He's part of Humans Against Gravity, a tettertroupe (teetertroupe sp?), and I believe either he or Darren Adam built the one I last saw them using.
I own two pieces of equipment from Unicycle-Voltige and trained on their tight-wires. Their props are ULTRA high quality and worth the freight fees. If you do order from them, be sure to have them subtract the TVA (taxe-valeur ajouté) -- the sales tax. 17.5 % in France. What you are buying is "vente a l'exportation."
On the declaration to customs, they will fudge the price so you don't have to pay duty-- if you ask them nicely. I had them ship my stuff as "personal effects" but I had to ask REALLY nicely.
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