Farfetched? Try this on for size: Levi Strauss jeans made in the early 1950s are now selling in Japan for nearly $2,000. Wearing 40-year-old jeans is the height of fashion in Tokyo. The craze supports a vast and growing industry involving almost 100 shops selling used American clothing. According to Japanese customs officials, 1,016 tons of used clothes were imported into Japan in the first five months of 1991-almost as much as was imported in all of 1990. The numbers reflect both the Japanese obsession with Western style and their fascination for the American cowboy. “They seem to have a longing for things from the Wild West,” says Hideyuki Kawamura, manager of Delaware, a Tokyo boutique.

Japanese collectors determine the age of jeans with the same exactitude as scientists carbon-dating fossils. At Delaware, for example, the owner recently examined a pair: he noted the real-leather label and an attached tag that read, THE RIVET’S STILL THERE. This is a detail only the cognoscenti would recognize. Levi originally used external metal rivets to hold on the back pockets, but customers who actually rode horses complained they scratched their saddles. In the 1930s the company began hiding the rivets inside the pockets. By the early ’60s they removed them altogether. Thus the owner verified that his find was a rare pair of pre-’60s Levi Strauss 503 jeans that had never been worn. (In those years the 503 model designated a boy’s size, which is especially prized among Japanese men because they tend to be smaller than American cowboys.) The owner promptly priced it at about $4,000.

Of course, such a find was like discovering a Turner in a yard sale. Dealers usually aren’t that lucky. Jeff Spielberg, a buyer of old denim in Santa Monica, Calif., usually pays between $50 and $200 for a high-quality pair of old jeans. He sells them to an owner of a Tokyo store for $150 to $500. The store then sells them for about $1,000. Most Japanese buyers travel to the United States several times a year to restock.

Finding the jeans in the States is a hushhush operation. Buyers don’t want people to know that Grandpa’s jeans can fetch such inflated prices. But as demand grows, dealers have been forced to go public with their search. Dollars for Denim, a Phoenix purchasing company for overseas stores, uses billboards, direct-mail, radio, TV and newspaper ads to attract suppliers. They buy denim jackets, too. “We’ll buy denim anywhere,” says Laurie Olson, the company’s owner. “I’ve even bought jackets from people’s backs as they’re walking down the street.” She says her yearly sales total almost $1 million; she exports about 10,000 pair of jeans a month.

Most of Olson’s jeans are less than 10 years old, but Tokyo’s hipsters don’t seem to mind. Japanese who can’t afford a pair of jeans that might have actually covered the seat of the Marlboro man will settle for ones that were worn to a mall in Santa Monica by a 14-year old high-school freshman. Olson’s company runs reclamation centers where they pay $10 for any pair of wearable 501 jeans without holes or stains. Some speculators buy new Levi’s 501s– $27.50 at JCPenney-and sell them to buyers for outlets in Japan, where they’re priced around $50. That is still cheaper than 501s exported directly by Levi Strauss, which can sell for $90 in Japan.

Understandably, Levi Strauss is unhappy with this parallel market. The company has responded by asking some U.S. stores to set a limit of about six pairs of 501s per customer. But Levi Strauss can’t enforce that policy because selling the product abroad at a cheaper price is perfectly legal. In fact, it’s the American way. “Hey, this is a free country,” says Olson. “I can do what I want.”

The idea of exalting something as ordinary as jeans astounds most Americans. They can now understand the way African tribes must feel when their everyday woodcarvings fetch high prices in New York art galleries: baffled, a bit bemused, but most of all, ready to start carving.

Telltale details, known only to the cognoscenti, help collectors date the jeans.

Outside copper pocket rivets from the 1930s

They moved inside (late ’30s–early ’60s)

A real-leather patch on 1950s 501 jeans

The tab’s ‘Big E’ stayed until the early 1970s

FROM JEANS COLLECTOR JEFF SPIELBERG, SANTA MONICA, CALIF.