The Chorus/Record assymmetrical 111 is usually rather expensive (but YMMV) - it's made and marketed to Record level, and just isn't very common. There weren't a lot of aluminum Record triple cranks made in the first place.

You can also use a current Veloce 111 BB (it's even affordable as new) on that Centaur crankset. I'm pretty sure they have the same dimensions as the Centaur BB.