It's not just a stage prop. It's an important cultural artifact. The Smithsonian has acquired the Parliament-Funkadelic Mothership for the National Museum of African American History and Culture. Admittedly, it is the 1990's replicate of the mysteriously missing original, but the Washington Post reports on the acquisition and its cultural significance and links to its April 2010 story about the missing original.
Smithsonian acquires Parliament-Funkadelic Mothership
The library has the Parliament album Chocolate City (CD 2309) referenced in the article plus lots of other material by Parliament, Funkadelic and group mastermind George Clinton.