Alternatives to Carpeting

My first 65 Valiant 100 had rubber floor mats and at 10 years old she had holes in the floor front and back on both sides.So bad I needed to put pieces of plywood over them so stuff wouldn't fall out. This was the second half of the 1970's when valiants could be had for 50 bucks and were still everywhere.DON"T USE RUBBER !
Thank you for the advice, I am happy that I asked, I do not want to cause any rust issues. Therefore, I will replace with a good quality carpet.