Thanks for the comments everyone.
Today I took my son for a driving experience at Thruxton and as part of the trip I dropped into Southbound trimmers to learn more about my carpets.
I took a couple of pieces of my carpet as well as the new carpet I had bought from them previously.
Southbound were very helpful and knowledgeable.
The first thing I discovered was that my carpet would have been Special Velour and not SliverKnit as I had previously thought.
Here it is in the original catalogue.
So the good news it I now know it is special velour 501.
The bad news is that Southbound have never managed to source an equivalent to this carpet and it is very different to sliverknit - so I can't purchase any new replacement pieces.
If anyone has a source of the special velour or some pieces of original carpet they would be happy to sell then please let me know.
This explains why it is very different in material form to the one I bought.
The new carpet is made from Sliverknit which seems a much softer and more plush material to the velour. It is also in Light Brown Armagnac which is a slightly later Porsche colour.
So the current plan is to try to patch the holes in the map pockets by robbing some of the carpet from elsewhere (as per jb's suggestion) and see how that works.
I have also purchased some of the fabric paint as suggested by misteralz to see if it will dye my carpet to lessen the faded areas. I have tried it on a small section to see if it will work - stay tuned!
Finally it looks like I will be selling the full SliverKnit carpet set in Armagnac - let me know if anyone is interested.