I can see why this hasn't been figured out before; the TF2 beta only contains a worldmodel for this weapon. But as it turns out, the Xbox 360 version of the game has a leftover viewmodel texture not present in other versions of the game!
I can see why this hasn't been figured out before; the TF2 beta only contains a worldmodel for this weapon. But as it turns out, the Xbox 360 version of the game has a leftover viewmodel texture not present in other versions of the game!