I think Triumph got it spot on when they designed these door boards for the GT6 Mk3. 
The bottom section is covered in moquette - a coarse type of velvet. The top part is vinyl with a welded styling line joining the two. 
The finished look is a bit more sophisticated than the Spitfire and really adds to the 1970's chic of the interior.
 
Includes:
2 x Heritage Door Boards - GT6 Mk3 style