And if you know someone, or can get, a standard 12" bubble you can simply cut it in the right places and use that. I have used this idea to produce canopy's for Sicroly, Blue Angel, Curare, Atlas and a couple of USA 1 C/L stunters. Your local hobby shop might even have replacement canopy's for 2m glider kits, Great Planes probably have hundreds of them. These are always useful for some of the 'straighter' types.
Evan.