Pick apart an old silk tie and use small clusters of threads held with glue. You won't get long stuff, but 10" is pretty easy to work with at a time.
Also, there are several styles of fletching "jigs" made out there that literally take minutes. My favorite it to punch a hole in the middle of a 2" square of thick leather, then take an old 3 blade broadhead, sharpen, and push it throught the hole. Viola' Perfect 120 degree feather spacing. making one out of wood is super easy, too, but getting it to mount them helical is tougher.