Probably going to have to make it. Goldberg could probably get you one from the kit version of the plane, but I can't remember if they are for sure the same. You could probably make one for $1.00 worth of hardwood or even some ply. Just epoxy it in and maybe put a couple of tri-stocks for back up. It's just a slightly tapered piece of wood (look at the notches in the fuse for shape) with a hole in the center for a blind nut. With the top wing also being attached at center, there isn't nearly as much pressure or torque at that point as you would find in a monoplane. Hence only the one screw. Be sure you have the ply doubler that glues to the bottom of the wing where the screw goes through too. Good luck.