Unlikely a natural breast augmentation result

I don't want to disappoint you but I would argue that at your relatively small frame you will not look natural with a 500 cc implant.  My decision of implant profile is simple.  The appropriate implant diameter for your body/ chest is chosen and the profile depends on the desired implant volume.  Assuming the appropriate implant diameter is 13 cm for you (which would be wide for most 5'4"/ 125 lb patients) then at 500 cc you will be in a high profile implant.  However, you will not look natural and will have unnatural upper breast fullness (some patients desire this).  In Mentor Memory gel implants, a moderate plus implant would be 400 cc at this diameter and a moderate profile would be 275 cc.