The parts were actually fairly easy to order. I went for the red and white X-Wing and it cost me just under £120 for all new parts (apart from those grey 12-tooth gears). I did end up using some of the parts from the official lego set 75301 which helped me out a bit, especially that cockpit piece.
There were quite a few of those 12 tooth bevel gears available on bricklink so they were fairly easy to get. I also decided to substitute the flat silver wheel pieces for light bluish grey as none of the stores I looked at seemed to sell more than one, and I also swapped out the inverted 1 x 3 tiles for normal plates (I’m not that bothered by the anti-studs).
Once the pieces arrive, and when I have time to build it, I’ll upload some of the pictures!