The bad news is that the 'Mk.III receiver' has totally bogus markings. All of those markings are faked.
It is a Khyber special sold as a souvenir to some GI Joe. The thing is actually a Mk.IV.

Good news is that it is probably a genuine Britishicon made unit that has been remarked for sale in the Casbah. It might even be in working condition.