I'm not sure about films, but you can try sanding and scuffing prints or photocopies, or whatever the original artwork consists of... Try it on a film! Maybe a brillo pad or steel wool would be good also, softly.
I'm playing around w/ some similar stuff right now actually. I will post if I have worthwhile results. Also, I knew someone that used to get some crazy looking textures by scanning w/ the top down on her flatbed scanner but w/ no actual image on the glass. Seemed to work well for her. Good luck.
My first acetate sheet got scratched up by the printer but I ended up using it alongside with the others - looked pretty good! It was a little scratchy and there were a few breaks but overall, I think it had a good 'texture'. Beats ruining your screen anyway.