They exist--I have several. In the past, the Custom Shop would sell double cream coils under covers. I do not believe they do this any longer. I'm on a cream kick...
Not true, I have a bunch of them in the past. The trademark (not patent) states cream bobbins, so the way around it is to build it with a cover. Then its nickel and not cream. A minor technicality. Have to order it through a dealer as a shop floor custom and expect to pay the price of that model pickup plus the surcharge of adding a cover.
I recently bought a set of new Seth's that where both double Creme under the covers... I know they use to randomly assemble the bobbins on these, but it appears they still do double Creme as they are only two months old.