Early publicity photos of Darth Vader (Duel's End) figure were shown as Darth Vader (Showdown). While it doesn't appear that the early design version made it to final production, there may be some Engineering Pilots or Salesman Samples created.
Original Design Box Art
Final Package Design
Here is a comparison between the early design and final package design.
If you find any preproduction examples, please post them in the comments!