It isn't very often the public has the opportunity to buy objects that have been to space.  Your latest chance ends November 30th.

NASA and the U.S. government as a whole work very hard to keep materials from and that have been to space under their control.  Heritage Auctions in Dallas have a few space items up for bid.  Including one interesting artifact from Apollo 13.

It's a notebook with commander James Lovell's handwritten calculations to guide the damaged spacecraft back to earth.  The notes were scribbled hours after the famous "Houston, we have a problem" phrase that is more popular than the event itself.

Apollo 13 captivated the world in April 1970 after managing to return to earth after a tank explosion crippled the spacecraft.  The Tom Hanks movie of the same name captivated audiences decades later.

For more see this source article.