I went out and got some of the zipper type, rather than the press type. I don't want to give them any cause for complaints. I think the TSA site actually shows the zipper type.
And at Houston Hobby someone is running business selling bags for 50 cents each.
(And can someone tell me WHY only CERTAIN types of quart bags are acceptable? Is the TSA getting a kickback? Is Kip Hawley getting a kick back... that would not surprise me!)