They are the same. Chances are, Simplex dropped the engraving later on in the production run (or, for that matter, earlier), and the non-marked ones you show in the photo there had Huret covers shoved onto it due to the original Simplex hoods having cracked (all too common), and consequently, being mistaken for Huret.

I've had one of these shifters without any engraving - that same non-engraved shifter had a severely cracked Simplex hood on it.

-Kurtr