Whoever steals, purloins, embezzles, or obtains by false pretense any key suited to any lock adopted by the Post Office Department or the Postal Service and in use on any of the mails or bags thereof, or any key to any lock box, lock drawer, or other authorized receptacle for the deposit or delivery of mail matter; or

Whoever knowingly and unlawfully makes, forges, or counterfeits any such key, or possesses any such mail lock or key with the intent unlawfully or improperly to use, sell, or otherwise dispose of the same, or to cause the same to be unlawfully or improperly used, sold, or otherwise disposed of; or