KMart's Bub2Be range has these great feeding tops that have an overlap of material around the breast area, so you pull one piece down and the other up, much like wearing a top over another top/ belly-band but easier as there's less fabric to deal with.
i love these! i have 5 of them and i have worn one each day (with a feeding bra underneath) since bub was born. i really should begin to extend my feeding wardrobe, but for now they are working great.