I reproduced this dagger in FreeCAD from a drawing a colleague gave me. It was supposedly worn by an evil Spock in the Original series Star Trek episode "Mirror Mirror": http://www.imdb.com/title/tt0708438/
It was meant as a halloween prop and, therefore, it does not come out of the scabbard. If you really wanted a dagger that came out of the scabbard though this could be easily remixed.
Printed on my custom Prusa i2 at 1.2x the size of the model. Sliced with Cura and printed from silver PLA at 205 deg C at 50mm/s.