Right now, I am researching a project about breast 3D reconstruction. Although I am not working with medical breast image, I will guide you up to my knowledge.
Lakshmi, I encourage you to try and generate some images yourself while you still search for the ones that will meet your specifications online. You would greatly contribute to knowledge to share such personal images with us.
best images are of our own patients and on our own machine as we dont forget images and our patients with whole scenario,this helps a lot while delivering a lecture on these images.