There are 1285 enneominoes and the solid forms would cover a total volume of 3x3x5x257 unit cubes. These could pack a variety of boxes - 3x3x1285; 3x5x771; 5x9x257. The 3x3x1285 is not possible as there are enneominoes which cover a length of four in two directions. Patrick Hamlyn has packed these solid enneominoes into a series of boxes as shown which together they can make a 3x5x771 box.
Peter Esser has also produced a series of boxes which together make a 5x9x257.
Peter has also made a series of boxes to form a 3x15x257 box.