Having a closer look at the 'new' bike during the week I discovered that the air deflector was actually jammed into position as the adjuster tabs had sheared off both sides.  I had a closer look this morning and thought of a way that might fix it.

Carefully lining up the broken pieces I had Ms. M slowly run a 1.5mm drill bit through the lug on the deflector and down into the tab about 10mm.   I found a snug fitting stainless nail, nipped of the head and sharp end to fit through the lug and into the tab.   Surprisingly, when I assembled the pieces the 'pins' held it all pretty square so I mixed up a batch of 5 minute Araldite which I ran down into the holes, then coated the mating edges of the deflector.
Thank goodness is was a half-way warm day here in Canberra so I did not have to stand around too long holding it all together before the epoxy started to go off. Some minor movement to get in square all around and then waited a couple of hours for the epoxy to fully harden.

I gingerly picked it up this afternoon to find the thing was rock solid and possible a bit stronger than normal due the 'pins'.  I fitted it to the fairing but had to dremel away a little of the epoxy to make it operate smoothly but it now looks and feel like a 'bought one'

I am not sure if this is a known fix or has been tried before but I thought it worth passing on.

Post some photos if possible?

OZ - I did a similar repair about 3 years ago, the deflector is still holding.