What you can do is build one out of foam . Make a drawing of cone on paper to scale and take the diameter at six or so points minus fiberglass and finishing .coupler for airframe , piece of body tube for the straight section .pull a few layers so once glassed out will be back to the correct diameter of the air frame .In at least one bulkplate for this nose cone run a dowel rod close to the size of the tip . I would also put a few holes in the bulk plates to run tubes up there .ie motor mounts .for nose weight electronics, ect . Hope that helps .