Not exactly what you asked but I just miked the nipples on my Shimano WH-R560 wheels and they measured 0.174" or 4.4 mm. That matches the sizes on the Park Tool's SW-14 "Spoke Wrench For Shimano Wheel System" which fits both 4.3 and 4.4 mm spoke nipple flats.

Based on my measurements and Park's description, I expect the Park SW14 or Shimano's equivalent is what you need. Note that these nipples are significantly larger than the common DT/Wheelsmith or Japanese spokes.