To the best of my knowledge the way those were manufactured the way colours were applied changed over years. I guess - from better to slightly inferior quality.
For some of the cars, eg. for our cars the original hood emblems had 113 stamped on the back side. Today you will not get those when you order from MB dealers, you will get the newer version.
What also may differ between emblems for various models is the dimensions and way of attachment to the hood.