Gruntal said it will buy Herzfeld & Stern brokerage.

The acquisition from Josephson International Inc. will make New York-based Gruntal & Co. the nation’s 16th-largest securities brokerage and investment banking firm. Josephson paid $17.5 million for Herzfeld early last year; Gruntal Financial will pay $4 million in debt, plus issue warrants on 2 million shares of its stock for the loss-plagued brokerage.