It is a mid-century Italian, Stoneware piece, not sure of the manufacturer. I was debating whether to keep it or sell it, and decided to keep it.....so I've been hunting for a shade on and off for a few weeks.
After trying about 20 various shades, sizes and shapes found one that I like, and which I think works - so thought I would share it. Pictured with the lamp is a Gerd Bogelund (Royal Copenhagen) stoneware bowl from the 1970's - a very special piece, and Boris! (a raku bull - only a few years but adds interest to the other pieces quite well)
I've got a wider view of this image and a few others on my styleblog if you want to have a look at them.