Snapz Pro 2.0.1 should do the trick. I'm not sure where you'd find an older version or if Ambrosia would still be able to register it (they should be able to; I registered 12 year old shareware ten years ago) but it would be worth checking out since it exports to QuickTime to create movies. It requires color, not sure of other processor requirements, but it does work with System 7 from what I've heard.