Attached Link: http://www.garciaaviation.com/insignia.html

If you scroll half-way down on this link from Garcia Aviation you can get a very good, accurate "AAF Officer's Cap Badge". You can use this for a maybe a bump-map too... Here's a link to more "Memphis Belle" photos. This is a fully restored B-17 that a pilot like you are creating would have flown... http://www.memphisbelle.com/bellegallery.html