For some reason I can't find a bag like it now, not even at the local nursery where I found it. While at the Habitat for Humanity Restore last week, I saw these mesh nylon bags that are the right size and material.
The bag has a fine mesh and nylon handles, so when it gets dirty I can rinse it out easily. The best part, aside from the price ($5), is that these bags were made from a recycled Habitat for Portland billboard advertisement. The tag explains how the bags were made from a billboard by a volunteer and the help of Spooltown.
Go to pdxrestore.org to find a local store, I found this bag at the Clark County store on 4th Plain Blvd.