And, instead of surgery, might I direct you to a Victoria's Secret or a Wonderbra from time to time?
The Wonder of Gel Satin Push-Up Bra from Wonderbra at Fresh Pair is available in sizes 32-36A and 32-38B (among other larger sizes) and utilizes built-in gel cups and fabric to create a bustier silhouette for your body.
A padded, racer-back bra or original Wonderbra will maximize your bust under a tank top.
The Wonderbra was designed by Canadian, Louise Poirier, in 1963.
The Wonderbra site takes the math out of the equation for you here.