Rubber insulation matting under the carpet- Replacement???

I've just removed the entire interior from my 91 clipper cabby. After removing the carpet I noticed that the rubber insulation/sound proof matting (which lives under the carpet) is missing on the drivers side. The passenger side is damp and there is none at all in the rear.

Here's my question……..
Where can I get replacements from?
and should there be some in the back?

Many thanks
Dan

You can replace it with dynamat, for sound deadening.

I have a complete set of Cabrio underfloor sections that have NEVER been wet, and have NOT gone brittle.

From a 1993 Cabriolet Collectors Edition.

PM me if you are interested, pick up from Norfolk NR17.