I have acquired one of these recently ( the one on the other site that Mark is referring to ) because it is an oddity . I concur that this is a dha and of Burmese provenance but probably not ethnic Bama ( not central belt anyway ) .
I will post some pictures once I have taken them . The length is about 27" with the blade being of fairly heavy contruction with an almost full length fuller and a shorter one nearer the spine . The hilt is black horn and the fittings around the hardwood ( possibly teak ) scabbard are brass. A faded thick orange/red cord cord wraps the proximal scabbard in an identical style to that done on other Burmese pieces. Although I have not personally seen this kind of dha before I have seen similar carved horn in the shape of a bird's head but inverted to form the body of a hand catapult ( the bane of authority and the choice of children : the other popular weapon in Burma
)
Currently I'm in the process of trying to get information from other Burmese sources about the age and manufacture of these . G C Stones pictures are 1930s so we can be sure that they are at least that old.
So far I have gathered that they may be ceremonial and used by an indigenous minority as a status symbol by a tribe who worship or hold particular significance to a pair of mythical birds . The only minority I'm aware of who believe that they descended from mythical Kinnari are the Padaung ( giraffe necked women ). Mainly the response is ," I've never seen one of these before" .
Here are a few pictures from Mark's site ( I'm sure he won't mind ) of dha of similar shape :
