If you have any friends that operate a machine shop, you could see if they could make something out of brass or aluminum with the idea of a film reel, but different proportions, so that you would have some strength. You could also have it made to look like there is film on the reel by painting it black and maybe making some fine grooves and then painting that section black. This would give a firm push area.
See the attached file for a reference image.
