There is a company called Dazon and they supplied a distribution company here in the USA called TANK, that went insolvent in 2009. They advertised a 350cc bike they called a KHAOS 350, Dazon has a website and they list products that have that engine and at the same 343.2cc.

TANK KHAOS 350


Here is another called Sunbeam offering the same engine on some of the models.

So behind DAZON is National Motors and they have had that 350cc engine for some time.