The Luke ANH and Luke ESB (or those two ANH sabers pictured) are NOT different graflexes. They "look" different because the clamp is rotated 180 degrees to the other side of the graflex flash. Since the clamp is rotated 180 degrees and people usually like to display the saber with the bunny ears pointing up, by definition the saber will be facing in opposite directions so that you can see either the bubble strip or the circuit board on the clamp.
Depending on the "hero" prop shots you're talking about (which can be debated):
ANH - If you have the saber displayed with the bunny ears facing up, the end with the bunny ears should be on the left of the display (IE it will look the the MR ANH you had pictured)
The clamp was placed in a different position for publicity shots from the position it appeared for the final filming. For publicity shots the clamp was aligned at a 9 O’clock position when looking at the saber from the emitter end, whilst for filming it was placed at about 2:30.
ESB - The other way around (like the top picture)
Personally when I display mine I keep them all facing the same direction (to the right)
Rebelscum has a great comparison and info on them all at: Link