To add or remove a gun from your license, or to obtain a duplicate pistol license, you must complete an Application For Amended Or Duplicate Pistol License and submit it with the proper fee to the Office of the Westchester County Clerk, Pistol Permit Unit, 110 Dr. Martin Luther King Jr. Blvd., White Plains, NY 10601. If you have any questions about whether this application is required, please call (914)995-3088 or email us at CC-PistolPermits@westchestergov.com.