That's kinda what I was thinking too Stick, they aren't endangered by any means just regulated and there is a term called "Wanton Waste" which means deliberately wasting edible portions of meat or other useable parts of an animal. Example would be killing a whitetail deer and just cutting the back straps out and leaving the rest, or cutting the head gear off and leaving the meat to rot, that's called Wanton Waste and it's illegal in most states. I know it sure is here and if the MDC catches you doing it you'll get a huge fine and maybe some shock time in jail.
With that explanation I just gave, there's no reason why any regulatory agency state or federal would want the feathers or any other part of a game bird to go to waste. As a matter of fact they should commend someone for using ever part of an animal or bird so nothing goes to waste. That's how the Indians were, they didn't waste anything, not even the bones they all had a purpose and they thought it was sacrilage or an insult to their Creator to waste anything. I still see it that way myself.
Glad you got some feathers and I hope your arrows turn out real good for ya.