This thread should clear up any confusion about Paul's basses.
This is a very early GUITAR of Paul's - a Rosetti Solid 7 - it is being played upside down and he has removed the pick-guard - a trend he continued throughout the sixties! Note the number of strings - just three, probably stolen from a piano!! Was this Paul's first attempt at playing a bass?! The picture was taken at Pete Best Mum's 'Casbah Club'.
This picture shows George and Stuart playing at the Top Ten Club, Hamburg 1961. Stu is still on bass, but if you look to the bottom left-hand corner you can see Paul's newly-purchased Hofner 500/1 "violin" bass leaning against the piano (it's just behind the Coke bottle!).
This picture adds further proof to the fact that Paul had his bass BEFORE Stuart left the band.
Paul playing his 1961 Hofner in the Cavern. Opinions vary as to whether the bass, which was purchased in Hamburg, was custom-made left-handed for Paul.
Filming Ready Steady Go, October 1963 - this was the last appearance of the 1961 Hofner in its unaltered state. The instrument had taken a bit of a battering, in fact the front pickup was held in place with a piece of tape! It was time for a replacement.
The Beatles, pictured in 1964, about to embark on a tour of Holland minus Ringo who was having his tonsils out. Paul can be seen holding his replacement Hofner 500/1 bass, purchased in 1963. Note the different placement of the pickups. THIS is the bass which he still plays to this day (although probably not live).
Here are the two basses in their un-altered states!
Here's where things get a bit confusing! In 1964, Paul had his 1961 Hofner repainted and repaired! As can be seen from this picture taken in 1964, a new mounting system for the pickups has been installed. Paul rarely used this bass though, and continued using the 1963 model throughout the Sixties and on!
Paul, pictured in 1966 during the Paperback Writer/Rain promo shoot. He is back using his 1963 Hofner; note that it still has its pickguard.
Further confusion about Paul's bass lies in the fact that at some point during their final tour in 1966, Paul removed the pickguard from his 1963 Hofner, as can be seen in this picture, taken on 21st August 1966. It is STILL the 1963 model.
From around the Revolver sessions onwards, Paul started using a Rickenbacker 4001S bass. This can be seen in various disguises in the promo film for Hello Goodbye and in Magical Mystery Tour's I Am The Walrus scenes.
For the White Album sessions, it has been mentioned that Paul used a Fender Jazz Bass, unfortunately I can find no photographic evidence of this, however this picture proves that the bass was used on later Beatle sessions - the date of thes pics is not 100% certain. (Thanks to Bobber for finding these!)
Paul dug out the 1963 Hofner model again for their 1969 rooftop gig! The large sticker at the top of the Hofner's body reads: "Bassman"!