What's my correct carpet style?

I plan on replacing the carpeting in my '72 Demon 340 that I've owned since 1991. I am the 3rd owner, the original owner having owned it for only 1 year, the 2nd for 18 years. I don't believe the carpet that's presently installed is the correct style (cut pile). Checking with a few of the carpet suppliers has yielded different answers. Some have said the early builds (mine is A27 or October 27th, 1971) used the 80/20 nylon loop, while others have said the correct style is the cut pile.

Who's correct?

Can anyone help?

Thanks!