What did you have in mind?
We were the first company to produce balanced line preamps, and they are all-tube.
BAT was one of our early customers before they started operations. They make balanced line tube preamps as well.
Aesthetix has long made balanced tube preamps.
IMO the better balanced preamps are also fully differential; if you google 'fully differential tube preamp' and 'balanced line tube preamp' you will get a long list of contenders.