Pamphlet staplers and soy ink

We are looking into heavy-duty staplers to staple covers to pamphlets.
We need to be able to staple through the fold (maybe up to 30 sheets)
and side stapling (maybe up to 150 sheets).  The stapler does not have
to be electric, but if manual must be easy to use.  Also must
accommodate stainless steel staples in varying lengths.  Does anyone
have suggestions, or experience with features which would be important
to consider?

An unrelated question:  Does anybody know what soy ink is and how it was
 or is used?

Please send any advice or info to: sinkule [at] nlm__nih__gov or call
301-496-8124.  Thanks,  Karen Sinkule (Preservation Section, Nat'l Library
of Medicine).

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                  Conservation DistList Instance 5:29
                Distributed: Tuesday, November 26, 1991
                        Message Id: cdl-5-29-008
                                  ***