I ordered the 13" linen drum shade by Finchel Shades in off white and it's just perfect.  I was a little apprehensive about the off white but it actually fits in beautifully with our chairs and I just love it.  It's very well made and clean looking.  It replaced an old shade on a lamp that I liked but the shade had to go and the difference one little detail change can make is amazing!  The shape, height and size fit the small 18" table so much better.