That's such a simple design that I'd be tempted to buy plain fabric and use a fabric marker to draw a design on it.

There is a site out there that I recently blogged about that you can print your own fabric.....

http://ruedevampdesigns.blogspot.com/2010/03/print-your-own-fabric.html

How big are the urchins? You can buy some decent plain linen from ebay for around $10/yd then get a large potato and some x-acto blades and make a stamp. Print the urchins on your fabric using some paint made especially for fabric. There's a great book on simple printing by Lotta Jansdotter, "Lotta Prints". Her esthetic is similar to these urchins. Ms. Jansdotter has spot on Etsy too.

Alternatively you could buy some $9/yd fabric by Amy Butler. While most of her prints are busy, she has a few that are more sparse, again, a similar esthetic. Amy has a website: http://amybutlerdesign.com
I'm thinking her "Optic Blossom" or "Modern Floating Buds"

ikea have one just like it, a wihte on black, or black on grey i think. saw it (in the uk) two weeks ago. hope that helps!

check out flowie similar look and feel half the price
http://flowiestyle.com/shop/cart.php?target=category&category_id=6

Take a look at Australian Aboriginal prints - the simplicity and structure are similar.

Either printing (potato or Gocco if you have one) or have you thought about buying some embroidery thread and trying it that way?

How many yards do you need? If it is just for seats, save up and do it.

You can print fabrics at Spoonflower, but check ebay--very often, designer fabrics are sold there.

Thanks for suggestions and advice! I never thought about printing my own fabric...I didn't think I would get good results, but all the tips are very encouraging!!! time to tackle the chairs ~ Liz

I have seen this very fabric for sale on eBay - just set up a search for "Groundworks" or "Urchin fabric."