Don’t know about Osanbashi Pier itself, looks like there is no shops for that purpose. Best is to ask Osanbashi Pier and the cruise company itself, Osanbashi Pier has website.
There is Yamato location two blocks from Osanbashi Pier. You can send it stop at that Yamato location and pick it up at. If cannot send it to the pier then I think sending package to Yamato shipping office two blocks away seems to be the best option.