Bruce,  I'm not sure of what you want.  Do you want a gauge that
measures air pressure and/or vacuum?  If so, are you looking for one
that measures pressure up to 100 inches of water?  If that's what you
want, it's fairly easy to find one on eBay.

I have several Dwyer Magnehelic gauges ranging from 0-0.1" of H2O up
to one that measures 0-100" of H2O.  There are several in that range
available on eBay right now.  Here's one for $50:

  http://www.ebay.com/itm/360450278218 

Regards,
Craig Smith