Randle said: “The book had actually been sitting on a shelf for a few months alongside lots of other 1970s memorabilia.
“I’d been planning to use some of the items in a fun window display, so it wasn’t something we’d paid particular attention to at first.”
She added that one afternoon she found herself “with a bit of spare time” and decided to work her way through the pile.
“It was one of the very last things I looked at.
“When I opened the book and saw Paul McCartney’s signature, I could hardly believe it… it was one of the best moments of my 10 years working in the shop.”
The book is signed on the inside front cover in black ballpoint pen by Sir Paul, reading: “All the best! to ye!”
Oxfam staff have so far been unable to trace the donor.
