Brandon Alinger says the sale was a "standout" moment during first day of sales at the auction.
Once wielded by Darth Vader, it is said to be "one of the most recognised props in the history of film".
More than 2,000 fans and collectors from around the world bid on items.
An auction house is also offering handwritten Oasis song lyrics and guitars for sale.
Francesca Lennon raises more than £87,000 by cycling between every children's hospice in the UK.
Francesca Lennon is cycling 3,200 miles to visit children's hospices across the UK and raise funds.
