Mercury Savings plans to buy a printing company.

The Huntington Beach S&L;’s Hermes Financial Corp. unit said it expects to buy Western Financial Printing Co. for $4 million. The purchase, which must be approved by the California Department of Corporations, is expected to be completed by the end of the month. Western Financial Printing, located in Santa Fe Springs, manufactures and sells passbooks, vinyl products, and other merchandise for banks and savings and loan associations.