Hello,
i have a pickup as the one you describe. It has Telecaster neck pu size , only more height because of the two coils. It has 4 conductors, but no cover - I think it was lost, I bought this pu used.
I guess, that it was made by Seymour Duncan but I can't find it in their latest products listing.
But I think, I saw it being made in a youtube-vidio about the Seymour Duncan factory.
Also take a look here:
http://forums.gibson.com/default.aspx?g=posts&t=22045
As you can read, I have no further information about this pickup, but I really love it. It was and will be again installed into the neck position of my early 70is Telecaster.
Best regards,
Till A