You are wise in doing your due diligence carefully in the selection of plastic surgeon for the procedure you are considering. Although good advice would require in-person consultation, it sounds like you may benefit from a custom-made silicone implant to “camouflage” the mild pectus excavatum. Sometimes, patients with pectus excavatum achieve a nice result with breast augmentation surgery only.
In regards to finding a plastic surgeon to help you achieve your goals, I would suggest starting with the American Society of Plastic Surgery and/or the Aesthetic Society of Plastic Surgery to obtain a list of well experienced board-certified plastic surgeons.
Only in person consultation will provide you with the detailed information you should obtain prior to making any decisions about proceeding with surgery. Ask to see lots of examples of their work and preferably speak/see patients who have had similar procedures performed. Learn about the potential risks/complications associated any recommended procedures.
You may find the attached link helpful to you as you learn more about options available for patients who present with pectus excavatum.
Best wishes.