to add to this one - another framebuilder I share my shop with had a whole lot of biplane fork kits made for him by a CNC shop. If you want to buy a set from him, I'm sure he'd be willing to hook you up cheap. you can email me at mechastudios *at* usa *dot* net. It's basically two steel plates: the lower plate has ovals cut into it for the fork blades, the top plate has similar recessed divots for the blades and a hole in the center for the steerer tube.