TMI sells foam and upholstery. Both LMR and CJ Pony Parts sell their upholstery materials. They claim the foam however t doesn't work under stock materials.
I'd be tempted to remove the covers and toss them in the washing machine to try and get the stains out, or hit them with a Bissel spot vac if you have one. The downside to a full restoration is you might drop $2K on foam and upholstery and they don't look original. For that much money, you can invest in better seats too.
As for Carpet, ACC is really the only game in town. You can read up on the reviews with regards to fit of their
[COLOR=revert-layer] carpets[/COLOR] and decide if that's the way you want to go. Rockauto.com sells ACC carpet for cheaper than the Mustang parts sites.
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