I bought one at kohls that is like a tank top but has a bra with actual cups and underwires. I bought it for the exact reason you described too and I like it very much. I couldn't find the exact one, but it's like This
. You have to buy it in your bra size (mine is 36C). Its supportive exactly like a bra but it gives you the smoothness in the back of no bra plus is tight and sucks in the tummy and love handle area. LOVE IT!