Morristown National Historical Park
30 Washington Place
Morristown, New Jersey 07960-4299

http://www.nps.gov/morr/

Note: A direct e-mail link is available on the Web site.

Has a document, in a file marked "Russian 1719-1835 (No 2851)" containing 23 pieces, listed as

"A DS by Alexander I, August 17, 1805, concerning Prince Avgust de Broglio-Revel."

See A Guide to Scholarly Resources on the Russian Empire and the Soviet Union (1990), p 91:

http://books.google.com/books?id=_qVNIw5TPcsC&pg=PA91