Antique Japanese Wooden Dragon Fish Drum

Lightweight wood carved musical instrument described as a Japanese Zen Buddhist dragon fish meditation or chanting drum, or 'mokugyu', featuring two dragon fish with a ball representing a pearl between their meeting mouths. (Drumstick not found as of time of posting.) It has some imperfections consistent with its age as shown in photos, clearly used at one point in time. Believed to have been purchased by the Burr sisters in the 1920s or 1930s.
 
Unusual design based on our online research as it is flatter (not as rounded) as most and its quality is somewhere inbetween the majority of  those we found, which were either much glossier and more expensive or much simpler and cheaper.
 
Material: Wood
H 5" x L 5 3/4" x D 3"
10oz