Brass coatings

I recently got a researcher request from a collector of microscopes in
New Zealand.  He has been cleaning and restoring his collection of early
19th century brass microscopes and has had to remove the lacquer.  He
wants to restore the finish on these brass instruments and is trying to
recreate the original finish.  He has even managed to track down the old
recipes for lacquer used by the manufacturers. He cannot locate two of
the ingredients:

    Dragon's Blood - Resin of Calamus Specie from a succulent growing
    in Socotra Island (sic?) -Gulf States.

    Red Sanders - Sandal wood.

Does anyone out there know what the contemporary equivalents of these
items are?

I know that coating metal artifacts is generally frowned upon.  Is there
any advice I could pass onto my researcher about proper care application
of lacquers to ensure that he does not damage his collection (and
investment).  Thank you

Alan Hawk
Historical Collections
National Museum of Health and Medicine
Armed Forces Institute of Pathology
Bldg 54, Walter Reed Army Medical Center
Washington, DC  20306-6000
USA

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                  Conservation DistList Instance 8:48
                 Distributed: Friday, December 23, 1994
                        Message Id: cdl-8-48-004
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