A carpenter or joiner would make them for you. A simple job for them.

Hi. Try untothislast website. They're based in London and they make all their furniture out of plywood. Not sure what your budget is but I think they're really reasonable. We bought our dining room table from them and it's great. Look at the bedside cabinets - or if you have a really tight budget you could just put up short shelves as tables which could look good and they are really reasonable. They are made bespoke so you can request a specific size too. Hope this helps!

If you like a bit of 'blue Peter' here's an idea !

Order corrugated cardboard from the Internet, glue all the sheets together , put a board on top and put heavy weights on top (evenly) then leave for a couple of days.

Then cut to size/shape with a saw. On this basis the item of furniture can be any shape or size you wish. This can also be done to create furniture legs. Varnish to prevent water and stains penetrating.

If required add a plywood panel cut to the size of the unit to finish the top off. Again varnished.