Does anybody know how to tell the differences between counterfeit series I&II pickups?

Let's see, how many Series I & II were ever produced - couple of thousand? How would that ever be a target for counterfeiters?
 
Perhaps the pickups from the Kawai copies might be employed, which were pretty close (but no cigar).
 
Check out the FAQ section which has plenty of pictures of the electronics, showing different generations and how they differ at the detail level.