Thanks (and I really appreciate your help in trying to locate one, the good karma will come back around )
If you do call up Cardas there is a good chance you'll talk to someone in the family so they might know. This could be a custom job, I know Cardas has made a custom Golden Reference HD650 cable for someone.
When I spoke to my seller on the phone I'm pretty sure he mentioned that the Cardas pamphlet mentioned the AT name and L3000 in there. We did spend a lot of time on the phone talking about random stuff, so I'll be able to give you my definitive answer (and pictures) when it gets here.