Attention all shoppers. Attention all shoppers. Watch for the blinking red light. For the next 15 minutes only, wills and divorces on sale at half price. That's right, wills, regularly $49.95, now on sale for $25. Uncontested divorces, regularly $200, now slashed to $100. MasterCard and Visa accepted. Attention all shoppers . . .

Red light specials on a broad variety of products and a virtual cradle-to-grave assortment of services are already familiar to customers at Zayer Department Stores -- eye checkups and glasses, driver training courses, bank loans, insurance for the family car and even dental work after the car is totaled.

Now, piggy-backing on the boom in storefront law clinics spawned by the 1977 U.S. Supreme Court decision permitting lawyers to advertise, the 250-store chain is planning to move into the legal market by the end of this year. It could well be a lucrative marriage of retailing and lawyering.

It would of course, be a no-frills proposition: No expensive art work on the walls, no banks of secretaries, no downtown address in high-rise buildings, no massive libraries. More like one receptionist and two lawyers in small, partitioned offices with, perhaps, a paralegal assistant and a credit card machine.

It also would not be a pioneer effort. In the last nine months, Montgomery Ward has leased space in 27 California stores to the nation's first and largest legal clinic chain, Jacoby & Meyers.

Zayer's plans to adopt the same market strategy used in California, based on a simple assumption: There are millions of middle- and low-income people out there who could use legal services but are afraid of the cost. The rich people can buy the services they need. Some low-income persons qualify for legal aid. But the average working- and middle-class families often are frozen out. Those people are Zayer's customers.

Richard Lawler, who is in charge of the one-stop shopping efforts that brought optical, banking and dental services to Zayre stores, also feel his customers don't use lawyers because lawyers often are remote, unknown quantities cloistered in fancy high-rise downtown offices.

"All people know is that lawyers are expensive," Lawler says, a problem Zayre's might remedy by posting standard fees for simple items such as wills, uncontested divorces, name changes or minor real estate transactions. Just having the lawyers in familiar and convenient stores will help overcome some of the remoteness, he feels.

One idea to keep costs down is to have pamphlets prepared on various legal problems and forms waiting to be filed out by customers before they go in to see a lawyer, Lawler said. The meter won't start running until the routine paperwork is done.

Some observers have complained that legal clinics often don't charge any less than the going rate. But Lawler is convinced that, at least for simple matters, the clinics will be cheaper than big-name firms. "And people will at least have a chance to get access to the legal system that they really should have but don't have now," he adds.

At this point, Zayre's is not only thinking of merely leasing space to a chain clinic, he said, but of possibly working out a relationship with leading firms in the chain's major market areas.

The key to making the concept work, as Stephen Meyers of Jacoby & Meyers found out, is volume and careful management. Meyers says that competition in the legal clinic business has lessened, while his own operations has grown to 75 offices in California and the New York City area, employing 150 attorneys. He has opened 30 new offices in the last month, 10 of them in Times Square Stores in the greater New York City area.

After the Supreme Court decision, "a lot of lawyers thought they could open legal clinics and become millionaires," Meyers said. Apparently it hasn't worked out that way. "Legal clinics come and go, and more seem to be going than coming." The expensive advertising may not always generate the business needed. After all, McDonalds couldn't make it selling two burgers a day.

Meyers said about half of his 75,000 new clients last year simply wanted to know if they needed a lawyer. The answer costs them $20, the initial consultation fee. If it turns out the client can use a lawyer, a written estimate cost for the services is then provided. A simple will would be $50, an uncontested divorce is $235 and up.

Zayre's is not wedded to any one concept of how to set up legal services, Lawler said, but he hopes to have the service in place in a few areas by the end of this year, starting with the chain's best locations. The Washington-area group, which includes 12 stores around the Capital Beltway, is clearly in the running, he said.