Many thanks to all who responded to my plea for ladder chain sprockets.
What a great community we have in the MMD.

I missed the obvious source, Player Piano Company.  They list three
sizes in their catalog.  Only the first number, stock item 1260, has
been discontinued.  Their prices are about one-third those of Stock
Drive whom I had checked out on their web site.

They have very strange rules for ordering, depending on who you talk
to.  The first two people simply would not take my order over the
telephone saying, and I quote, "It would tie up the telephone line."
I just thanked them and called back until I got someone who _would_
take my order.  He informed me that if I had over 12 items I would have
to fax the order in.

Richard Vance sent the name of Hale Brothers, Inc, who have been making
ladder chain for over 100 years!  I called them and they stated that
they have never made the sprockets, always relying on Bridgeport or
Boston Gear, but they are still very much in the chain business.  They
carry a line of Delrin sprockets.

You can find Hale Bros. at http://www.halebros.thomasregister.com.
There are spec sheets on all the sizes of chain that they make.  The
demand for ladder chain has declined drastically in the last 10 years.
Timing belts and stepper motors seem to be the culprits, or so I was
told.

Once again, thank you to those who responded.  The ladder chain problem
appears to be solved and I learned much by asking.

Ed Gaida
egaida@txdirect.net