By Douglas Thompson A rare archive of photos and memorabilia giving an extraordinary insight into the birth of The Beatles is expected to fetch millions of pounds. Auction houses are vying to acquire the collection of over 600 images and letters from the estate of Stuart Sutcliffe, the band’s original bass player, dubbed the lost Beatle. Items include photos of the early group, with Stuart and his best pal John Lennon. Stuart left the band in 1961 to pursue a career as a painter, leading to guitarist Paul McCartney taking over on bass. An extensive portfolio of Stuart’s artwork is also being o…