The body, minus the wheels, engine and rear axle fetched more money than its roadworthy equivalents at the auction.
Auctioneer Richard Edmonds said: "I think we had some very keen bidders at the sale looking for a restoration project."
A total of 16 Austin 7s were sold in the auction.
The Austin 7 was one of the most popular cars produced for the British market with more than 290,000 made between 1922 and 1939.
But Richard Edmonds Auctions, which ran the sale, said a Morris Model G taxi, the last of its kind, failed to sell due to a lack of interest.
The dusty, dented and neglected body of a 1930s Austin 7 car has been sold for £18,480 at auction after sitting in a Gloucestershire barn since the 1960s.