Suggestions for repairing seat base

The area beneath the bottom of the front seats on my LR 110 is looking tatty. It seems to be made of black cardboard and has torn. I am not sure what the proper name for this is to source a replacement. I can find the corner protectors but not the main item. All suggestions gratefully received. Thank you.

Some just replace with thin carpet cut to fit, the sort of stuff they use on shop floors that is tough and hard wearing. On mine I just took it off and left it bare.