For those ones I choose not to use the US Army insignia as a base. While the USN 'gold stripes and a star' scheme is an international one found in many navies around the world, with only few variation; the 'bar(s)/leaf/eagle' one is a very specific one...

For those I admittedly choose the easy way: using the navy ones, only replacing gold by maroon. However, one detail leaves me unhappy: was I to make tactical insignia, i.e. black on camo ones, IN and IM would look exactly the same. To mark the distinction,...