Gun to your head, if you were forced to staff a post office with flightless birds, which kind would you pick? Personally I'd go with ostriches, because they are both tiny of brain and aggressive of temperament (plus their long necks would reach high shelves and they would be very fast at delivery). But the good people at Stonewheat & Sons are clearly cowards, because they picked kiwis, the little avocado-shaped birds of New Zealand. Although, bonus points for featuring cassowaries as mail carriers, a species whose first Google autocomplete suggestion is "cassowary attack".
KeyWe feels like a name that was generated pun first and ask questions later, which is a design method I have immense respect for. In this case, your two little kiwi pals must run a small regional Telepost office that has almost terminal levels of whimsy. The telegram machine is split into separate groups of keys that spin, swap places, and, worst of all, do not follow the standard QWERTY layout. Packages are labelled according to the personal notes enclosed with them: set up this scarecrow as soon as possible, but remember his stick body is very fragile. The mail room is also run by an octopus.