Not being funny, but how about possibly considering Paul McAndrew - the kitman of 30 years at the club?
Although not directly involved with the team, he obviously has good access to them in his role and am sure would have good stories to tell from the time.
Think you'll be lucky to get any ex-player involved, to be quite honest, unless they were a fringe player in the squad at the time - like Nathan Dyer or Liam Moore.