Anyone have any idea where to get one of these? I've been looking for one for my son but can locate one anywhere new or used.

Sterling pipes don't come up for sale very often and even distributors don't put them on their site since I'm not aware of any shop that stocks them. You'll have to call a Shires distributor (or Shires themselves) and place the order most likely. Wait will probably be at least 4 - 6 weeks though; maybe more, I don't know what their current production schedule is like, especially now that they moved factories a few weeks ago.