As it is, many of the the Sugino parts have a three or four character designation, ending in a "B" (Harris hyphenated them but it's not that way on the part).
On the store page, it says that the "B" means bolt (some old BB spindles have a threaded portion on the end sticking out for a nut).
I think they don't want them on the store page because it will lead to inquiries about a part that is no longer available.