Now that you mention that musical train set, it tickles my memory
just a little; I can't remember what the original was called, though.

A search on eBay showed a few of "today's" version.  Go to eBay and
search for "Melody Train Set".  Battery-operated, and instead of
replacing ties, you adjust little slides on each tie to play a tune.
Not a bad idea.  The eBay item number is 6011771044.

Bill Mackin, Iowa

 [ At http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=6011771044 
 [ "Music and Fun Melody Maker Train Set.  Adjustable music notes
 [ to create different melodies."
 [ -- Robbie