An extra DVD has been added to the Knebworth 1976 commemorative set. In fact it is given as a gift with anything you buy from the site, including just a poster or T shirt and can be viewed on the home page of www.rockmusicmemorabilia.com
Thanks for the link, which I've looked at. I'm not clear though on whether there is a DVD, (or CD for that matter), of the Stones set. I'd buy it if there was.