What do you mean by 2 piece? There are bridges that are parts mounted to a single chassis and there are bridges that have individually mounted tailpieces 1 per string. There are bridges with 2 or 3 adjustments but it's hard to tell what you mean by 2 piece.
I think the Warwick bridge qualifies as a stop tailpiece bridge, can anyone verify if thats terminologicly right? anyway, do you need a replacement bridge for a Warwick or you have another bass with a 2 piece bridge (Alembic for instance) that needs replacing or you're building a bass and want to know where to buy a 2 piece bridge for it? sorry for putting you through questioning, you just didn't specify your needs and you didn't fill your profile (go ahead and fill it, RIGHT NOW!).
A matter of semantics, I guess. Jerzy Drozd calls`em "two piece"... (click)