Hi Tom,
I believe that the style of the sticker changed before the rim was changed to the heavier (extruded) version. I have a rim in stock that is the earlier (lighter) style but with the new style sticker.
As far as identifying the two types. The newer one has a taller profile and a raised section on the tire gluing surface.
I also have a nos example of the Mavic Sport rim that you asked about in stock. If you want to call me at the shop tomorrow I'll weigh it for you. 631-262-0909 - 11:00 until 4:00 east coast time.
Jamie Swan - Northport, N.Y.