Speaking of ISI, they have an interesting series called the Library of Modern Thinkers:

This series offers authoritative introductions to the thought of leading intellectual defenders of ordered freedom whose ideas have influenced the development of a conservative intellectual tradition, as written by leading contemporary scholars who are themselves authorities on the thinkers about whom they write. Each book includes a bibliography, chronology, and other appropriate critical material.

the volume on Robert Nisbet. They also have volumes on Ludwig von Mises, William Ropke, and Eric Voeglin. They are planning volumes on Michael Oakeshott, Bertrand de Jouvenal, Andrew Lytle, Francis Grahm Wilson, and Will Herberg. Worth checking out if you are interested in intellectual history and/or modern conservatism.