Matthews Studio Equipment Group has signed a letter of intent to buy a Cincinnati-based rental concern in a $4 million cash, stock and debt assumption deal, company officials announced Monday.The Burbank-based lighting and grip equipment suppliers’ acquisition of Haehnle Dwertman Inc. will expand Matthews’ operations into the Ohio, Kentucky, Pennsylvania and Indiana markets. Allen Haehnle will remain in Cincinnati as president of HDI. “The addition of HDI grip and lighting business to Matthews will complement our grip and lighting business,” said Carlos DeMattos, prexy of Matthews in a statement. “Expansion into the important (HDI markets) offers growth opportunities for other Matthews product lines,” DeMattos added. Monday’s move follows Matthews’ announcement last month that the company had signed a $12 million deal to acquire Albuquerque, N.M.-based equipment supplier Duke City Video. Matthews’ stock closed Monday at $2.62, up 12.5¢ in NASDAQ trading.