craftgrrl | in search of speckled fabric...

My SO is almost finished painting his new office, and is looking for window shade fabric that appears speckled, like his desk. It's various greys, and looks like someone used a toothbrush to speckle the different colors on top of each other. We've been to a few fabric stores (Jo-Ann, Rag Shop) and I've also Googled "speckled fabric" with no real success.

If anyone can give me a heads-up on where I might find fabric like this (type of material is less of a deal, but he's got a specific "look" in his head), I'd greatly appreciate it.