Apparently off the last 4-8-4 NP bought. Lots of photos and interesting writeup if you're not collecting.

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... &rd=1&rd=1

According to my steam whistle collecting friends, the eBay record for a steam whistle fell THREE TIMES in the same week.

The idiocy started with a former NP brass/bronze short-bell six-chime that sold for $5,100:

http://cgi.ebay.com/np-northern-pacific ... dZViewItem

followed shortly by that ex-NP long-bell Hancock for $5,200 (note: it's gold-painted iron, not brass, and certainly not unique to NP); and finally:

http://cgi.ebay.com/Southern-Railroad-3 ... dZViewItem

for a Southern Railway top-levered short-bell three-chime, with some subsequent rebuild work on it.

Furthermore, the apparent eBay record for an air horn has also just been set: a Nathan M5 for $3,001:
http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... %26fvi%3D1

There have been one-offs, ship whistles, and exceedingly-rare H5 and N3 horn sets that have sold for more privately that we know of, but these are records for things you may have a prayer of actually seeing--or needing, for that matter.

As my friend, one of the top whistle collectors/authorities in the world, said to me, "The world has gone mad."