Get pampers cruisers "size 7" or bambo nature size 6: https://www.diapers.com/p/bambo-nature-diapers-899560
Even a size 6 huggies will probably work. Pampers have really stretchy sides and just stretch them out before you put them on or attach them first and then pull on. 28" waist should be fine. Look online for cheap cuties size 7 or comfees size 7 as well