scratch around the farm junk pile maybe you find something useful
my pressing die is a piece of schedule 40 PVC- then I found a heavy steel plate off an old cultivator - its an end bushing off a pivot beam and has a short piece of heavy tube welded to the face - my PVC die is a pretty neat slip fit in the steel tube - soon as I press it swells the PVC just a tad till the steel ring holds it - soon as the pressure is released it slips out - no contact with the steel so no contamination of the meal -
I would take a piece of 90 mm PVC schedule 40down the engineering supply shop and hunt for a heavy steel tube that it fits neat but not tight - only need a little piece three inches or so then load your meal into the PVC - you make a bottom piece from masonite or even a plastic disc - make some plastic dividers - can press 4 or 500 grams at the time in thin pucks - when its done push the whole column through the plastic die using a spacer under it (90mm DWV will do for that)