Thank you so much for the reply, much appreciated.
Regarding the first generation trem bars, although they are no longer available, did they have an external thread which screwed into the nut shown in my second picture? I'm guessing that they must have, otherwise there would be zero point in the nut being there. There are a number of threaded aftermarket bars available so I'm wondering if one of those would fit, unless of course Line 6 used a different thread to everyone else!
The trem set screw is available but only at Full Compass in the States as far as I can make out , sadly though they won't ship to the UK judging from other posts on this forum that I've read.
If I keep the guitar, I would like to discover what the spacer fix for the model knob is as well but the way I'm feeling, although it would cost me a lot more, I'm leaning towards returning the guitar and getting a new one, that would probably work out about the same as getting a 2nd gen bridge for mine and solve all of my problems in one hit.
I really appreciate the contact information you gave me, that is extremely helpful, thank you very much indeed.