Here is another one that was sold on the Oriental Arms site. A massive dha described by Artzi Yarom as follows:
"This Huge Dah sword is the biggest we have ever seen. Monstrous blade 38 inches long 3 inches wide, forged from good steel and with sharp edge. Wood handle bound with braided rattan ring 22 inches long 2 ˝ inches in diameter. The wood scabbard is bound with rattan bands. Total length 64 inches compared to an average of 35 inches in a more common Dah swords. To demonstrate the dimensions we are showing this monster next to a “normal” 33 inches Dah sword. ... Several of the rattan bands are a later replacement. Very unusual. Probably Burmese, late 19 or early 20C. ceremonial sword."
This one might be Burmese. It is quite plain and obviously intended for serious use.