Thanks so much peeps. I've since abandoned the idea of lossa Stubbies. I asked my local exhaust guys about a custom fabrication like this:
I also emailed the guy who built this bike, and he gave good feedback on his exhaust setup. He just used 17" reverse cones (a bit like emgos), chopped the headers to accommodate the pipes, and secured them to the frame. The exhaust shop said they'd custom build something similar for $500, which is also tempting.
I'm just too worried about the D&D race tt's ground clearance to risk it (otherwise I'd buy them in an instant!). Aussie roads are just too potholey
I'd love their performance boost and aesthetics, but I think I'd leave them behind the moment I go over a speed bump.