I am almost certain that the action shown was Broadwood's own creation.
In his book, "Restoring Pianolas," Arthur Ord-Hume describes this as
"a slow action, hard to service and with poor repetition" (Plate 17).
I have had direct (and not very happy) experience with the upright
version of this action and I couldn't agree more!  I've also had less
experience with a grand that from memory looks identical to the one
on eBay.

I can tell you that the Broadwood action was really crude and
inefficient.  Moreover, it is so bulky that it had a reduced compass
just so that it could be accommodated within the piano case.  Also, the
grand piano action was modified with the backchecks not on the keys but
on (I think) a separate lever between the key and the whippen.  This
made the piano action more difficult to regulate.

I would refuse to work on one of these Broadwood players again; the
results are just too disappointing.  I certainly wouldn't buy one!

Stephen Powell
New Zealand