I have been off the list for a few days so I don't know what other responses
to this question have been, but here is mine:
We often use another type of polyethelene foam, brand name Astro-Foam from
Astro-Valcour, Inc.  It is supposed to have the same archival properties as
the Volara but is in a slightly different form, often referred to as a micro-
foam I think.  Not as perfectly smooth as Volara but far cheaper (and still not
terribly abrasive, either.)  I don't have inforamation about contacting the
company directly but our supplier is a local paper products company;  when we
get Volara a local plastics company orders it for us.  Some calls to these
kinds of suppliers in your area might turn up some sources.
Hope this helps.
Anny
Thompson
NC Museum of History
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