Certainly a mixed piece, and as Ariel has stated 'when' is the ultimate question. Obviously if the 'mating' was recent .... it would be disappointing.
Bearing in mind mind that the blade is resin fixed, the blade should have been easily attached. But it doesn't sit centrally within the langets
and would not fit a scabbard properly (the langet would catch on the throat as there is little space between one of the langets and the blade)
However, you cannot dismiss the possibility that this 'union' is older.... and if it were....would be extremely interesting, as I have never seen this combination before.
Regards David