John Lennon's toilet.

John Lennon's toilet to be auctioned with Beatles memorabilia.

John Lennon's toilet, one of the items to be auctioned at the The Paul McCartney Auditorium at Liverpool Institute for the Performing Arts Photo: PA

A mono-sound copy Two Virgins, which he recorded with Yoko Ono, is expected to fetch at least £2,500.

When the avant-garde LP was released in November 1968 it was notable for being sold in brown paper bags because the sleeve controversially featured a naked picture of the famous couple on the cover.

Although a limited release of 5,000 stereo versions of the album were available in shops, fans had to write to the record label to purchase a mono copy of the record.

The exact number of mono copies sold is not known, but auction organisers say it is likely to be as few as a ''couple of hundred''.

As a result, the sale, part of the 33rd annual Beatles Convention in Liverpool, is attracting record levels of interest.

The auction is also inviting bids for Lennon's toilet from Tittenhurst Park, his Berkshire home between 1969 and 1972.

Lennon told builder John Hancock to keep the porcelain lavatory and ''use it as a plant pot'' after he had installed a new one.

It was stored in a shed at Mr Hancock's home for 40 years until he died recently.

The toilet carries an estimate of £750 to £1,000.

Stephen Bailey, a Beatles expert and organiser of the auction, said: ''The toilet might be worth something, and it might not, but it is certainly one of the more unusual items we've sold.''

Mr Bailey, manager of the Beatles Shop on the famous Mathew Street in Liverpool, added: ''I have only ever come across two other mono copies of Two Virgins before so that will be the one to watch.

''Even at the end of the Sixties, during such a bohemian period, the picture of a naked couple on the album cover still caused a great deal of scandal.

''The stereo version sold relatively few copies at a time when any one of the Beatles could easily have shifted hundreds of thousands of records.

''It must be one of the rarest Beatles solo albums to come up for auction.''

Also from Tittenhurst Park comes a small harmonica that belonged to Lennon's son, Julian.

Again it was given to Mr Hancock by the musician who asked him to take it home as ''Julian was driving him mad with it''.

Lennon told Mr Hancock he would tell Julian it was lost.

The harmonica is expected to fetch between £750 and £1,000.

Fans of Sir Paul McCartney can bid on a black and white photograph taken of the budding star outside his family home, 20 Forthlin Road, Liverpool, when he was aged about 21.

The estimate is £375-£400.

Other lots include an early concert ticket from September 28 1962, when the Fab Four played the Royal Iris Mersey Ferry.

It is valued at £2,500.

And a full set of Beatles autographs could go for anything between £1,000-£2,200.

For Beatles collectors on a budget, less expensive lots include a 1966 ticket for Mathew Street's Cavern Club, where the band made their name, which is expected to fetch between £60 and £100.

Mass-produced memorabilia created at the height of the band's fame, such as Irish linen tea towels and China plates, are valued at around £20.

Mr Bailey said interest in the Fab Four is on the rise as fans prepare to mark a series of 50-year milestones, such as their first performance in Hamburg, Germany, which was marked last week.

There are a total of 295 lots being sold in the auction, which will take place next Saturday in the The Paul McCartney Auditorium at Liverpool Institute for the Performing Arts from 10am.