Hamilton Changer problem – interesting problem

So I got a call about my changer stealing someones money.  I threw the switch on the coin hopper and it was jammed.  It just looked like a normal jam but it was only one quarter.  I had to take it apart, which seemed odd.  While inspecting the problem I noticed that a screw was jamming the hopper (third picture).  It was very bad luck because it should have fallen out the crap holes (forth picture).  The screw came from the bill acceptor flap. 

I can’t decide if I want to replace with a stainless guard or another factory plastic one?  If anyone has the stainless guard installed please send me a picture.  Thanks.