Tyler Corp. has entered into an agreement for the sale of its wholly owned subsidiary Hall-Mark Electronics Corp, said Joseph F. McKinney, chairman and chief executive. The acquisition will be made by a new corporation owned by Hall-Mark's current management, headed by Jack A. Turpin, Hall-Mark's founder and chief executive. Los Angeles-based Riordan Freeman & Spogli is organizing the transaction and will be a major equity investor. Hall-Mark, based in Dallas, is a major national distributor of electronic components and systems products. Tyler, also based in Dallas, provides goods and services to industrial customers.