WDP does not sell space frames at this time. You can buy them from private individuals, but it usually costs about $120 (although I got mine for a mere $60
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I live in the US, but I've done this mod. It's extremely easy, all you have to do is cut away a little bit of metal at the back of the frame and drill and tap a hole. If you've ever used a dremel before it shouldn't be any trouble. Actually, I think I have a diagram laying around that shows exactly where to cut at (somebody else asked me for instructions, so I made a rough diagram), email me and I'll send it to you.