Thanks to all who responded to my request for the fiberglass eraser
refills.  Especially thanks to Craig Smith and the others who
supplied a link to The Eraser Company.

I called the company and found them to be extremely helpful in
identifying the product I was using. Within three days I had 2 new
holders and a package of 25 refills delivered to our door.  If you
are interested, here is the info:

  The Eraser Co. Inc.
  P.O. Box 4961
  Oliva Drive
  Syracuse, NY 13221
  E-mail: info@eraser.com
  http://www.eraser.com/

The tool (holder) is part nr. AA0020.  The refills (pack of 250)
part nr. is AAA0014.

Craig also suggested a small layer of glue on the area of a glass
sliver will allow the removal when the glue dries.  I haven't tried
it as yet, but you bet I will.

Thanks to all,
Bob Oppenheim