SilverWook said:
http://www.youtube.com/watch?v=A-hHwQ32UoE
Actually, they used a Boba Fett figure, (large and small) for all of it. Boba was standing in for the Biker Scout, as an action figure of it didn't exist yet, and was the one character similar enough in design to the scouts.
Point is, it's the same situation - they used another character as a placeholder because the new character's final design was still being worked on at the time.