Lyric sheet for 1967 single is purchased in Los Angeles
Liverpool site has got some replicas instead
Beatle recorded 'Imagine' using the equipment
Council considering honouring Pete Best and Stuart Sutcliffe
Former Beatle says he's not keen to write an actual autobiography
Songsheet is expected to fetch $200,000 (£122,000) in US
Paul McCartney, John Lennon and George Harrison signed the document in Hamburg
Site had sold songs for 25 cents each
Fresh threat has come from local authorities
Drummer will play six dates with his All-Starr Band