I heard a reply from the OP:
I just received a reply from B and K:
"It has an old European/USA connector and we no longer supply them, the best solution would be to remove the socket and replace it with a modern connector or even hard wire it, this would*have to be carried out by a competent person*and the unit safety tested and certified after conversion, we cannot offer this service."
I'll look into changing the connector.Although B & K products have rivets everywhere..
So, it appears to be a bastardization of NEMA with EU standards. I'm not sure how the difference in voltage works though.
Thanks people.