Somebody  chomped our feeder end cap  and tore it off the feeder, so I threw  together something in Openscad.  It  doesn't have all  the fancy hook/eye bits that the original did, just a big groove that press fits onto  the remaining bits sticking out  from the  feeder  tray.  So  you'll  want  at least outdoor tape and maybe some caulk to hold this in place. It has holes   to fit  5mm   screws for a   perch  or  other accessories, and  you can add  more holes or  attached  bits   if   you  want.  (The extended perch in the photo is  not part  of this file,  it's from  <https://www.printables.com/model/361344-bird-buddy-front-perch> I  think)