how are you with Pep files? I have one that would probably work, but it looks a bit of a pain to make. (Ive not made one from it)
You could probably pep up some of the parts and add a piece of dowel or plastic tube for the barrel.
Or even use the side views to template onto double thickness 12mm foam or something.
Please note: I am not the creator of this file. I'm not sure where I got it, however I have only ever downloaded public pep files, so I assume this is ok to share. If anyone claims to be the creator and wants me to delete this post, please let me know.
The pep file is the wrong model,it's from Judge Dredd,i don't think there is a pep for this it's the original comic mk2(mk1 only had one mag) i think.
It shouldn't be too hard to make(i started one years ago,never finished)the problem areas are the barrel end and the scope adjuster/scope