The big boy pipes, when filtered -- Peterson, Rattray's, Stanwell, Big Ben, etc. -- use a standard-length 9mm filter filled with charcoal, capped on one or both ends with ceramic. So not just rolled paper. Available primarily in Europe, these can be alternatively filled with meerschaum chips. I have both on hand. On the other issue, even Savinelli's (balsam) wood filters capture more than moisture. In my Savs, the used filters are always brown and wet... and of course expensive.
As a suggested alternative (carbon), piper shops have products to put in the bottom of any pipe bowl for absorbing and cooling. Fish sold separately.
Not just for specialized Erik Nording pipes, the volcanic clay bits can be placed right n your bowl, or in the Peterson System reservoir:
http://www.pipesandcigars.com/pipe-filters/85358/eriksen-pipe-keystones/#p-120396
A reusable clay body (one piece) can be dropped into the bowl:
http://www.pipesandcigars.com/pipe-filters/77122/philtpads-10/#p-126700
Many retailers have these, try 'em with your next pipe/tobacco purchase?!