Had only now noticed your post. I might still have the measurements from a Federal contract Kepi from the old Wallace Zearing collection. I had planned to make a reproduction of it, but a divorce around that time derailed those aspirations. I will try to dig around for it, but can't make any promises as to when I'll lay my hands on it, or if I managed to keep it after all these years.
If I do find it, I will convert it into a pattern... maybe I'll finally get around to making one for myself!