in the us theres a brand of camping equipment named coleman. they all manner of stuff including kitchen supplies, they make a chamois cloth thats super absorbant, looks exactly like the material paul had in his revo. i have used it in the exhale lung for about a dozen dives w no issues. it comes in a big towel so i cut it into a smaller piece.
google 'coleman camping' youll find it., look for model#827-255t
Coleman - Camp Towel-Personal Care
that link may work too.