you know ... now that you mention it: neither did i! i was way undercaffeinated when i posted that - and i think amazon is incorrect: the official release i own is a double CD, not a CD + DVD (it's the First Barbarians Live from Kilburn that's a CD + DVD)
but the Largo 79 footage has been circulating for ages as a bootleg called Buried Alive, so if you ask on the "hot stuff" forum i'm sure someone can help you