Christies is auctioning plaster casts of various panels from the Parthenon Frieze. From the information given, it is unclear whether these are a first generation cast (or more probably a second or third generation cast) of the originals.
You can view more details on page 79 of the e-catalog for the auction (linked to from this page ). There are also copies of some sculptures from the Acropolis that I noticed in the catalogue.
Country Life 
Take a piece of the Parthenon home
Friday, 5 October 2012
Christie’s is selling more than 350 items from James Perkins’ collection at Aynhoe Park, including a piece from the Parthenon in Athens
Eclectic artefacts amassed on ‘a modern grand tour’ will be sold at Christie’s South Kensington on October 9, when James Perkins, owner of Aynhoe Park, sells more than 350 items to make room for more pieces in his constantly evolving collection. There’s everything from an armadillo-shell helmet (estimated at £600-£900) to a stuffed walrus head, plus furniture and photography, but pride of sale is the magnificent Classical plaster sculpture.
Mr Perkins’s fascination with sculpture began when he was 15 and saw a newly cast bust of Apollo being drawn from its mould in a restorer’s workshop in Cheltenham. He saved up his pocket money, and the bust became the first piece in his collection, which includes 12 sections from the Parthenon frieze, attributed to Brucciani & Co (£6,000-£9,000). Viewing days are at Aynhoe Park, Aynho, Oxfordshire, on October 5-8 (www.christies.com).