Tangential, but maybe of some use: I have an old book press with a large wheel on top for screwing it tight. Before I got my Potter medium press (which I love), I used it with Matrix / Silhouette dies. It worked fine for those, but – speaking for myself only here – I do not think I would have enough strength to use a pancake die with it.
When I used it for matrix dies I would use a layer of acrylic sheet the size of the press (12" x 12"), rubber cut into shapes (as Richard Sweetman shows in his video on forming), the metal (copper in those days) usually 22ga, the die (3/8" thick), and then another sheet of acrylic.
Not sure if old book presses are easier or cheaper to find, but I thought I’d pass along my experience.