dressing screens

Hospital / first aid suppliers will do a tubular metal frame one, which you could then cover with your own choice of material.

That said, a couple of old zed-beds and a dangle grinder you could make your own.

Or a selection of old doors (stained glass would be nice) and some hinges. If you stick some triangular blocks of wood in the hinge edge to stop the doors 'closing' more than 135deg it will help stop the thing folding and falling over.

Owain

A few bits of hardwood, a few hinges and some fabric to cover it (or paper if you're feeling Japanese).

A non-Changing Rooms style MDF one ?

Screens aren't popular these days, as there are few modern rooms big enough to make one usable. You can find antiques, you could have one made. MDF in a hardwood frame isn't a bad choice for construction though. I've also seen a very nice fabric-covered one made by framing panels cut from cheap Chinese cheong-sam (cheapest source of silk you can find)

Shoji is actually a bad staring design for a screen. Shoji is sliding panels that are supported by a tight-fitting groove top and bottom. Take them out of the grooves as a free-standing screen and they're much too flexible.

You might also find that an extra-wide rail at the bottom of a screen (Victorian ones typically use 6" width, as opposed to 2" verticals) makes it more stable, by lowering the CoG.