Just wanted to thank everyone for the advice and tips on this post...
My manual gear knob (non illuminated) was scratched and chipped, probably due to the previous owner wearing a wedding ring or something, and the leather started to pull away as well. It looked and felt awful. I found a replacement on eBay (an illuminated one

) for £45 and, thanks to you guys, I had it changed in less than half hour! I didn't need to take out the centre console out as I'm not worried about wiring it in just yet, so it was just a matter of replacing the knob itself. I'm so pleased I found this forum...
For those that may be interested - I had to look to see if the old one comes apart, and it does very easily. If you want to just replace the plastic "3D" part at the top, you can. You need to slide a very fine pry tool (credit card will probably do) into the front between the plastic and the leather, and it will unclip. Gently pull it back, wiggle it around carefully, making sure you don't snap any plastic clips, and it comes away in 3 separate pieces. If, like my new one, yours has a little dust in, you can also do this to clean it out.
The next thing I'm going to do is replace my Bronze/Rose Gold centre console with a Dark Aluminium one (with the help of advice on another thread on this forum) and I'll wire my new shiny knob in so it lights up at the same time 💡😜
Cheers guys