Soghd? Kai Yuan T'ung Pao coin

Vladimir Belyaev
July 12, 1998
Diameter: 22.6 mm
Weight: 2.2 g
Obverse: Kai Yuan T'ung Pao
Reverse: plain

Kai Yuan T'ung Pao is one of the most common of Chinese coin legends. It was issued during Tang dynasty from 618 AD and in some other periods of Chinese history.

But coin dealer said me that this coin was issued by Soghds.
It is known that the Turghis Khanate issued currency by imitating Chinese Kai Yuan T'ung Pao coin but legend was in the Soghd (Sogdian) language. It's questionable for me, did they issued coin with Chinese legend.
Any additional information will be highly appreciated.

Chinese Coinage Web Site