Members of the National Council on the Arts, the presidentially appointed body that advise the National Endowment for the Arts, are considering setting up a nonprofit corporation "which would make clear that government support of the arts is the best thing that ever happened to the arts," said council member and New York producer Hal Prince.

The Endowment faces the prospect of a 50 percent cut -- the Reagan budget proposal for fiscal 1982 -- and the possibility of being revamped into a quasi-governmental organization, one of several ideas that a newly formed White House task force on the arts and humanities will discuss. The task force, to be composed of private citizens, will recommend ways of finding more private support for the arts.

Some council members are concerned that the new task force will recommend altering the structure of the Endowment. So the council is considering setting up the nonprofit organization of private citizens that would oppose any such recommendation from the task force, others at the meeting said.

"It's in no way intended to be a fight," said Prince yesterday after returning to New York from the council meeting here this weekend. He added that the much-talked-about corporate support of the arts "is not the answer. It's wonderful, but the corporate support has climbed astonishingly because of the Endowment. The fact that the White House doesn't mention that stuns me."

Prince said of the proposed nonprofit corporation, "I think the whole thing is going to happen with a speed you won't believe."

Other sources said there is no definite consensus on what to do. But some council members were so committed to the idea of the corporation that they offered to personally contribute money. Prince was one of them. "You bet," he said. "We're going to need some dough. I'm going to put some in." There was also talk among members of seeking funds from friends.

All of these discussions took place during closed sessions. Several council members wanted to wait and see what happened with the White House task force. Early Saturday, White House official Aram Bakshian spoke to the council and tried to assuage its fears. Bakshian told the council the task force "will be fairly good representative group that you will find heartening."

Bakshian later told reporters that the task force was "not an attempt to make an outside structure [to the Nea]. In fact some of the staff of the Endowments may be drawn upon."

Council member Willard Boyd, president of the University of Iowa, had said, "The council is anxious to be of assistance. This is a great opportunity to review the importance of the arts."

Prince commented yesterday that Bakishian's speech was "sort of a polite attempt to ameliorate things, to tranquilize us. I've said I don't want to be party to euthanasia. I said [to the council] we were being tranquilized."

Another source stressed that the council members "don't want this to be seen a rebellian against the White House. Margo Albert [a council member and an actress] cautioned them to be as polite in their approach as possible."

Albert and member Franklin Schaffner, the Oscar-winning director of the film, "Patton," are both supposedly being considered for positions on the White House task force. The two deny having been asked officially yet, but both confirmed this weekend that they talked with actor Charlton Heston -- one of the co-chairs of the task force -- about 10 days ago.

One thing the council did officially decide on was the recommendation that $1.3 million from the fiscal 1982 administration budget of the Endowment be transferred to the state programs categories. The NEA was critically questioned by congressmen this week on the agency's plan to increase its administrative budget for fiscal 1982 in light of an overall 50 percent cut. The council's recommendation must now get NEA chairman Livingston Biddle's approval.

"I think the council felt that even though the administrative budget relates to actuality nand a limited staff," said Biddle, "the states were particularly in need of help and we should make every effort to reduce the administrative budget by about 10 percent. I'm going to look at the administrative budget again very carefully."

At this weekend's meetings, the council members, again acting as private citizens, bounced around such attention-getting ideas as planning a day when all museums and theaters would go dark in appreciation of the arts and a honk-your-horn-for-the-arts day. (The latter was quickly rejected by the group.)

And to "add insult to injury," in the words of member Norman Champ of St. Louis, the White House called Biddle Friday "and said the Endowment has to pay for the [White House] task force. You can make sure I'm going to do my part to see that they don't get a nickel."

What the White House requested was staff and clerical help, according to other members and Biddle. It is unclear whether or not the White House wants funds as well, said Biddle.

Champ said yesterday "they're asking us to help dig our own graves. It's like asking Marie Antoinette to pay for the tumbril." He added, "We've got to stop taking this lying down. We've got to stop being patsies. The administration is out to get the arts . . . Ronald Reagan is asking all these businesses to give to the arts and he, himself, only gave one percent of his income. There isn't anybody in this room [where the council was meeting] who doesn't spill more than that in contribtutions to the arts."

Biddle commented later, "I know the council is very concerned about their responsibilities toward the arts . . . I'm going to tell [the White House] of the council's expressions of concern. I'm going to say I will make staff available if they want it.