The likelihood of finding replacements of the Welte Vorsetzer damaged
wooden stack, etc., is about 1 in 25 million.  Your best bet would be
to restore what is there and make what must be copied.  Wood worm holes
can be filled with carpenter's glue and pneumatic cloth glued over the
holes.  A good wood mill can copy any other parts.

We have to do this in the restoration business all the time.  I have
done several instruments where the water damage was so extensive that
major parts had to be copied in new wood.  The Vorsetzer is rare enough
it should be worth the extra cost of restoring it.

D.L. Bullock    St. Louis
www.thepianoworld.com