For a price gauge........This member is selling a factory Turbo spoiler with the engine lid. The engine lid looks like it was a regular one that was modified, and not an original Turbo lid. Price started at $650 and recently lowered to $500.
http://forums.pelicanparts.com/porsche-911-used-parts-sale-wanted/506020-factory-turbo-tail-f-s-650-00-a.html