The aged firebrands of Sunset Hall are engaged in what could be their last battle.

These are the people who manned the barricades in the 1930s to unionize the workers of America. In the 1950s, many of them struggled against McCarthyism. And in recent years, the old folks, some of them in walkers, piled into a van to demonstrate their support for Jesse Jackson's candidacy and to take part in the Los Angeles teachers' strike and the strike of Eastern Airlines employees.

This time the battle lines are different. On one side are the people charged with the old folks' care who, beset by dwindling occupancy and financial losses, have decided to shut down their home later this month. On the other side are the oldsters, who see themselves as the latest victims of an uncaring society.

Hanging in the balance is Sunset Hall itself, a Los Angeles institution that for 66 years has been one of the country's few retirement homes intended specifically for aging radicals.

"It's the loss of a very important people's institution," said Sadie Tomkin, 89, a longtime communist and a former manager of "People's World," a Communist Party newspaper, who has lived at Sunset Hall for nine years. "If this were a decent society, this would never have happened."

Ann Maupin, president of the Board of Directors that governs the home, said there is no choice. "We're not happy about this, but we feel that, economically, we are simply not able to go on."

Founded in 1924 by members of the First Unitarian Church of Los Angeles, Sunset Hall was established to house elderly "religious liberals" who share the Unitarian's philosophy of intellectual open-mindedness and religious tolerance. In 1965 the facility moved a short distance east to its present location, a 19th-Century Spanish-style house with 36 rooms surrounding a shaded patio and goldfish pond on Francis Avenue in the city's Mid-Wilshire district.

Although operated independently, the house is just two blocks from the majestic stone church that for years has been a major center of social and political activism in Los Angeles. The retirement home is governed by a paid membership of 240 that elects a 13-member Board of Directors. While the home is set up as a nonprofit corporation and receives no money from the church, the majority of its board members and many of its residents are Unitarians.

Over the years, Sunset Hall has been home to some of the city's best known radicals.