When he was here, during his 22 years as chairman of the Senate Judiciary Committee, there was almost always some kind of flap around James O. Eastland and his style.

But now, even with his retirement to Sunflower County, Miss., there's another flap - this one over the five-foot-tall portrait of the Mississippi Democrat that hangs in the committee's hearing room.

The Arlington artist who did the portrait, Charles M. Mount, has sued the University of Mississippi Foundation in a nasty little dispute over his payment.

In a suit filed recently in U.S. District Court here, Mount is seeking $13,450 from the foundation in payment for the portrait and a smaller rendering that was sent to the university in Oxford.

Mount's suit was filed after the foundation sent him a check for $3,000 - money raised by Eastland's friends at home - to cover his work.

Dr. George M. Street, a member of the foundation's board of directors, said the artist's suit came as "a shock and a surprise". Street said last week there would be no further comment "until we have seen the bill of complaint."

Controversy was the last thing Eastland's friends around the Senate expected when some of them decided last year to immortalize him on canvas.

"I think I instigated the portrait. I thought it would be a nice thing," said Francis C. Rosenburger, who at the time was the Judiciary Committee's staff director.

"We raised $3,000 for the portrait. I never talked to Mr. Mount about an amount above that. I would have been frightened away if it had been $13,000," he said.

Mount visited Eastland's office, drew sketches of the senator, took photographs of him at committee hearings and came up with the portrait that now is in the Dirksen Senate Office Building.

Before Eastland retired last December, a veteran of 36 often controversial years in the Senate, the portrait was presented and hung in the hearing room.

The smaller version was sent to the university archivist at Oxford. It eventually will be placed on display there, possibly in the university law center named for Eastland.

Mount, meanwhile, according to the suit, took out a $5,000 loan from a Virginia bank, with the expectation of paying it bakc with his fee from the foundation.

A December statement Mount sent to Street listed the cost of the two paintings and imported frames at $13,450, but said that by agreement with Rosenberger he would accept $5,000.

Although he apparently had no written contract, Mount asked for the full amount with interest, plus interest on his bank loan, in his suit.

"We paid him every cent that was contributed by the senator's friends," said Rufus T. Jones, director of development at the university. CAPTION: Picture, Charles M. Mount's painting graces the Senate Judiciary Committee room. By James K.W. Atherton-The Washington Post