Oh yes,  there were Ampico player parts sold in the Steinway.
Check out the Encyclopedia of Automated Musical Instruments by
Q. David Bowers for pictures.  Notice in the old ads featured in
past AMICA bulletins from overseas that show Steinway as a brand
with Ampico.

Don Teach

 [ The Steinway factory in Hamburg was not bound by the exclusive
 [ agreement to provide only Duo-Art players, thus many fine
 [ Hamburg Steinways were equipped with the Welte-Mignon player.
 [ -- Robbie