A document dated Nov. 30, 1911, and sent to Sunbeams Music Trust by Paul McCartney in 1990 as a response to a donation request, bears the signature of one E. Rigby, a scullery maid who worked at Liverpool’s City Hospital.

Sunbeams exec Anne Mawson put the paper up for auction at London’s Idea Generation Gallery, where it is expected to fetch £500,000 (US$750,000). Sunbeams provides music therapy for people with special needs.

Mawson told BBC News she hung on to the document, a salary register, because it touched her when she received an envelope with McCartney’s world tour stamp on it nine months after she asked the ex-Beatle for a donation.

“I opened it and inside was this beautiful, ancient document,” she explained. “It was spine-shivering really. Partly because he had responded in such a personal way.”

Guitars owned by Cliff Richard and Sex Pistol Glen Matlock will also be on the block at the Nov. 27 auction.