Send me a PM with your address. I'll give you a piece cut from a roll. It's bulk filter media and a $52.00 roll is several lifetime supplies unless you restore a scope or two a week.
Edit: For those who are do-it-yourselfers, here is one (of many!) sources: http://www.grainger.com/Grainger/filter-media-rolls/filters/hvacr/ecatalog/N-8xw
Edit again: I'm a wee bit lysdexic. I was thinking 543. It and the 555, 556, etc.. take a 1" thick filter. You can get bulk filter media in thinner form for the scope that do not have room for a 1" thick filter. But, a box is a vast quantity and fairly expensive. For thinner material, a clever trick is to use Scotch Brite. Thanks, VintageDave.