NEW YORK (CNN/Money) - Don Johnson always gets the car. In Miami Vice, he got to drive brand-new Ferraris. In Nash Bridges, it was a '71 Plymouth.

Which had the bigger price tag? Hint: It wasn't the Ferrari.

That's right, a real 1971 Plymouth Hemi Cuda Convertible (Nash Bridges drove a fake) can be worth as much as $1 million, according to those who track collector car values.

That's $1 million if you can find someone willing to sell theirs, which will be tough, given that only 11 were produced that year.

Muscle cars, those high-powered gas-guzzling American coupes built between the 1960s and the mid-70s, are fetching huge prices at collector-car auctions.

This "clone" of a '71 Plymouth Hemi Cuda convertible is owned by Paul and Patty Wright of Advanced Restoration and Collision of Huffman, Tex.

"The muscle cars are definitely having their moment in the spotlight," said Tim McGrane, director of marketing for the auto auction company, Barret-Jackson.

But one standout is the Hemi Cuda, not to be confused with an ordinary Plymouth Barracuda. Convertible Barracudas are relatively common, even ones made during the 1971 model year. The name Cuda -- without the first two syllables -- was reserved for cars with higher output engines. The name "Hemi" comes from the car's engine, named for its hemispherical combustion chambers.

Makes with fewer than 500 cars are considered rare, and of the 11 '71 Plymouth Hemi Cuda convertibles made, only seven were sold domestically.

The production numbers were so low because there was little demand for drop-tops in those days, especially on a car like the Hemi Cuda, said Tom Collins, an editor for Krause Publications who's editing a book about Chrysler muscle cars.

Muscle cars, with their huge engines wedged into mid-sized car bodies, were made for racing, not leisurely cruising with the top down. Driving around in a rag-top was the sure mark of a poseur because the added weight of the car would have reduced its speed.

One of the 11 made in 1971 is still unaccounted for, said Galen Govier, an expert on Chrysler cars and parts. The missing car is rumored to have been scrapped in the mid-1970s by a Phoenix owner who wanted to sell the car, but found buyers at the time were only interested in hard-tops.

Since so few of these cars exist, the $1 million appraisal value attached to a really outstanding example of one of these cars is difficult to verify and is largely a combination of theory and rumor. These cars don't appear at auction very often.

Chuck Engleman, a former executive with Kruse International, said that he bid on a '71 Hemi Cuda in rather poor condition at an auction about four years ago. He lost the bidding, but that car went for $400,000, he said.

One of these cars was sold privately within the past two or three months, according to Barret-Jackson's McGrane, who said he understands that the car was, in fact, sold for about $1 million. Robb Myers, founder of RM Auctions, another prominent auto auction company, said he also had heard of the deal from "very reliable sources."

According to Govier's account -- also, he says, from "reliable sources" -- the deal was never actually completed.

Million-dollar deals for classic cars -- even multimillion-dollar deals -- are rare but not unheard of. In August 2002, a Cobra Daytona Coupe sold for $4.4 million.

But muscle car values are shooting up fast. Earlier this year, Dean Kruse, president of the auction company Kruse International, released his annual "Dean's List" of cars he expects to increase most in value this year. Of the 10 cars on the list, all are American makes and five, not including a Corvette, are muscle cars.

For those very few who own of these cars, it's not about the money, said Brett Torino, a Las Vegas-based real estate investor.

"It's just extraodinary. It's a piece of art. It's American art that you drive," said Torino of his car collection.

Torino, who says he owns at least 20 Chrysler Corp. muscle cars, is one of the very few people to actually own a '71 Hemi Cuda convertible. He bought the partly dissassembled car last year for an amount that, he says, was less than $1 million. (Torino's claim of ownership was verified by other sources familiar with the car's purchase.) Torino also recently purchased the car used in the Nash Bridges TV show.

"I don't think too many people buy these cars for an investment. They just have a passion for them. Then there are the bragging rights," said Torino.

The value of the cars has been increasing, said Torino, because enough people his age -- he said he was in his mid-40s -- have become financially successful to spend that kind of money on them. The real selling price of a car like his has probably surpassed $1 million, he said. He claims to have gotten several offers over that for his car.

"I don't think anyone today would sell their Hemi for $1 million," he said.