Things about this auction don't feel right. Aside
from the serial number being blurred in the
photo, from Googling all day, it appears that
Guernsey's auctioned off a bunch of Coltrane's
stuff via eBay (including Dolphy's flute) in
2005:
"Dolphy's alto, bass clarinet and flute were sold
but I cant remember the price."
http://www.saxquest.com/forumThreadView.asp?ForumUID=7&ThreadUID=10320
This would jive pretty well with the story that
seller has about the flute being acquired twenty
years ago.