It's possible that they are Ian Burgess' photos.. he of Friends of Fairport.
I've bought photos from Ian in the past.. they look similar.
They're a bit early for Ian, Amethyst, I think he always says he didn't start "properly" until the late 80s, perhaps 88/89. The posed/publicity ones look like John Woodward's, at least some of the live are Garry Hunter's, and there's even some of Doug Lake's from the Gladys sessions. Looks to me like they may well be from Peggy's Woodworm clear-out rather than from a photographer's/crew member's collection.