One of the most unusual strikes in the history of area labor relations in moving toward a confrontation, as Raleigh Stores Corp. this week expects to replace the chain's striking employes.

Pitted against each other in the 10-day-old strike is the growing 25,000-member United Food and Commercial Workers Local 400 and Raleigh's, the area's largest independent clothing chain.

The strikers in this case are atypical, many earning $20,000 a year or more. Many are veteran salesmen who for years have served a steady clientele of the area's well-to-do.

On the other side is Raleigh's, the 11-store chain with 1979 sales of about $55 million and a new worth of about $10 million. In more than 35 years of union representation, Raleigh's has never had a major union confrontation. In the background are industry rumors of a possible sale of Raleighs later this year, which management denies.

The labor clash erupted now because the union feels it has run into a stone wall, at a time when incomes have been sliced by inflation in a costly region. The company, on the other hand, says that for years it has been giving in to union demands and that 1980 is the year for that to stop.

"We've made our final offer," a Raleigh's official insisted the other day. The firm claims it is being singled out by Local 400 in an effort to show union strength.

"I am more confident than ever that the union is using Raleigh's as an object lesson in this strike in an effort to organize their unorganized stores," said Leonard Cohen, Raleigh's lawyer.

Not so, union officials and striking workers retort. "Everyone staying out says the company is refusing to grant us any additional pay in the next three years even with a normal inflation rate," says one striker.

"It's take it or leave it under any circumstances, and that's not bargaining."

Although there are a number of key issues, including pension provisions and Sunday work shifts, the crux of the dispute is wages. The company is offering to raise base pay by about $5 a week and will not discuss raising the 8 percent commission rate unless between now and March 30, 1980 "the composite hourly rate" for any division is not at least 8 percent greater than the equivalent rate for the one-year period ending March 30, 1980. The union says that provision is unfair and gives commission salespeople no assurance of a pay hike.

After the old contract expired on March 30 and after several unsuccessful negotiating sessions, federal mediators were brought in to try to resolve the outstanding issues. Last-minute efforts by the mediators failed on April 24, and the strike began the next day.

Union officials say sales at the stores have dropped dramatically and business at the stores appears to be slow. Raleigh's, noting that about 450 of the 576 union personnel have not come to work, says business has been good during the middle of a spring sales push. "I'm not saying we're making our figures, we can't expect that," said Brainard Janicki, Raleigh's vice president.

One indication that Raleigh's is feeling the pinch was the firm's sudden but unsuccessful attempt Saturday to seek a temporary restraining order in D.C. Superior Court to block further picketing at Raleigh's stores on Connecticut Avenue and at Mazza Gallerie.

Fashionably dressed picketers have appeared at all 11 stores since the strike began on April 25, and yesterday, the union set up mass picketing at Tysons Corner and Montgomery Mall.

Raleigh's told striking employes last Monday that unless they returned to work by May 2, the firm would "begin to employ permanent replacements" and that they would have "no right to work unless a vacany occurs."

The company has published an advertisement seeking replacements saying that salespeople could earn $26,000 to $35,000 during their first year, a claim that has only fueled the strikers' bitterness.

Further adding to the uncertainty surrounding the strike are persistent rumors in Washington retail circles that Raleigh's is on the verge of selling the chain to Hart, Schaffner and Marx, the huge Chicago clothing manufacturer and retailer.

Raleigh's President Sidney Lansburgh has vehemently denied that the sale is in the works, and other officials say the rumors have nothing to do with the strike. Officials of Hart, Schaffner refuse to comment, but their visibility in Raleigh's offices recently has fueled the gossip.

Any deal between the companies cannot take place until June 1, the expiration date of a 10-year-old Hart, Schaffner agreement with the Justice Department that bars new acquisitions.

The deal is a logical one because Hart, Schaffner, with thriving retail outlets across the country, has long-standing sales agreements with Raleigh's and would be very interested in operating an outlet here, one of the few prime markets where the firm does not have a retail subsidiary.