I suggest the following individuals be contacted as potential sources
for a missing comb:

  Nancy Fratti  <musicbox@sover.net>
  Al Meekins    <al@antiquemusicboxes.com>

At the Regina factory, the double comb machines had their combs tuned
together as a set.  Additionally, the tuning of Regina combs varies
from one machine to another -- one cannot merely swap these combs
around and expect the tuning to consistently track.  Therefore, some
tweaking of the tuning would have to be performed once a replacement
comb was located.

Alan Fox
Antique Melodies Museum