I was originally looking for some "Z" brackets or some flatstock that I could bend into shape as a basis for making the brackets when I stumbled on some heavy duty gate hinges in the hardware store and, lo and behold, they were almost the perfect shape and size for this little project. Made by a company called Starx (product #43.103.27) 60cm gate hinge. I sized them up and at six Euros each I figured it was a pretty low risk investment if they didn't work out.
Turns out they were perfect. I made a quick template and cut and shaped them with my grinder, and drilled out the holes for the clamp bolts and turn signals. A little black spray paint and Voila!
