Can the "cowboy look" once again lasso big fashion bucks this fall?

Fringed jackets and vests, flounced "prairie" shirts, plaid shirts, jeans, leather and suede, cowboy boots and hats - all these are among the offerings appearing in stores, catalogues and ads for the coming season. And both designers and retailers are counting on this look to stir up fall sales.

Why the cowboy? Claims Ralph Lauren, whose fall collection for women - with a heavy dose of cowboy elements - sparked much talk about the look, "I just sense this is what people want. They are looking for land, want an outdoor life which is quite western. Those are the vibes I'm getting.

Those "vibes" have been around a long time. Witness the success of stores such as Counts Western in Washington, and the overall growth of jeans stores selling many of the basic parts of a western look.

"It's theatrical expression," says Koko Hashim of Neiman-Marcus. "There's the cowboy look, and there is also the glamor look, the military look, and lots of others. It's a way of escaping from the rigidness of our lives. It's a natural move after a period of very tailored sportswear."

But the western look may well have its roots in past European collections.

There have been cowboy boots, cactus prints and other "Old West" prints in the Zandra Rhodes (from London) collections for more than two years. There were great fringed sweaters and jackets in the last Sonia Rykiel collection, and fringed leather styles from Claude Montana - both from Paris.

Fashion mavens in Paris and St. Tropez, who have taken to wearing cowboy boots with their jeans, have without doubt brought on the fashion of mid-calf boots which is bound to be popular this fall. And in last May's round of Paris ready-to-wear shows for the fall Yves Saint Laurent took the unique kind of tooling used on cowboy boots and applied it to a leather jacket.

But nothing quite so inventive for Mr. Lauren. He says he has gone back to the original cowboy style. "What I did was to take the things you could only find in an old Gary Cooper movie - but that never existed in any store, even in a western store - done well in good quality rather than cheaply."

What makes the look modern, says Lauren, is that it is worn with a mix of other clothes. ("It is important that you not look like you are going to a Dale Evans ranch," he says.)

Hashim, who has just moved to Dallas and is also a fan of the American cowboy, has another possible explanation for the look: "The cowboy is the last of the rugged individualists, the last of the non-corporate man. He isn't touched by the 'in-ness' of anything."

Designer Bill Blass has a simpler interpretation: "By far, the best dressed person in our country is the cowboy."