Dimarzio killed off the Model G pickup, which might be what Granny Gremlin is thinking of?
Artecs do indeed have wider spacing. I discovered this when I tried to stick one in the EB-0 bass. I would hesitatingly say Artecs are spaced to go in the neck position of Fenders.
I'm guessing Artec only sold them because somebody had commissioned them for a bass? For example I'm noticing a lot of cheap Chinese Filtertron/Fidelitron type bass humbuckers available at the moment, and those Chowny basses came out recently with these pickups fitted. Likewise I'm wondering if the Artec mudbuckers were devised for the B&CH EB-2/Rivoli copy bass, or some other far-east wonder like the Italia or Fret King basses? I'm guessing that it cost a wee bit to tool up to make them, so it would be worth it to make a bunch of them!
All that, and the Artec was a diarrheabucker...