Or, rather, there were. The last ones to come up for sale sold almost immediately, so me telling you that you could have bought Mal’s shirt and pants, or Inara’s outfit from the last scene, or an Alliance Pilot’s uniform if you had only noticed them in time would just be cruel.
However, you should take this as a suggestion to start monitoring The Prop Store of London a little more closely. And apparently in the middle of the night.
The Prop Store of London has a fair selection of other items posted, including a “money heist bag” for $500. If your just want one for the look, and not worried about it having been in the movie, its a standard olive-drab US Air Force helmet bag. You could get an identical one for about $20 through a military surplus store.