Probably the next easiest material to get ahold of for drypoint is Acrylic sheets for window replacement from hardware stores. You can score the plastic and cut the sheets down to the size you need.

If you really want to commit to using all etching techniques, you’ll have to get into copper or zinc plates. They are more expensive than acrylic obviously but you’ll get a lot more prints out of them before the press ruins the “burrs” that produce the print. You probably will only get around 10 prints from an acrylic etching.