The following is a list of clothiers and whose prim breasts they support. I will do my best to keep it complete and accurate, and invite additions and corrections.
At least initially, I won't include the prim breast makers themselves, who all make at least some tops for their products. I include Smashing Prims and Titillation because their emphasis is on the clothing; each outfit of interest to us includes prim breasts textured appropriately for the outfit.
Also, again recall that where we refer to support for Implant Nation, we mean the "multiclothing" and "universal" prim breasts.
Amazon Designs: eCorp, iBoob, Icon, Implant Nation, Sensations
Big Breast Sluts: Implant Nation
BL Design: Implant Nation, Sensations
Boobie Tops: eBoobs, Implant Nation
Busty Goddess: Implant Nation
Clothes by Ricy Babii: Implant Nation
Epic Proportions: eCorp, Implant Nation
MinkaMade: eCorp, Implant Nation
Nanami: eCorp, iBoob, Implant Nation
Princess Tops: Implant Nation
P.S. Design: Implant Nation
Ravishing Racks: eCorp, Icon, Implant Nation, Lolas, Sensations
Schuffel+Schism: eCorp, Implant Nation
Simply Orgasmic: Implant Nation
Smashing Prims: Smashing Prims
XXL Top Design: Implant Nation