Bob Russell spotted the cream-colored British roadster on the online auction site while surfing the Internet.
It was stolen from outside his Philadelphia apartment in 1970 after he returned home from a second date with his future wife, the Associated Press reported.
"The fact that the car still exists is improbable," he said. "It could have been junked or wrecked."
Russell, 66, a retired sales manager, has searched for the car ever since it went missing.
On May 11, during a routine check on eBay for his beloved motor, Russell saw it listed for sale by a dealer in an online auction.
It had a final bid of $19,700.
According to ABC News, Russell knew it was his car because the vehicle identification number matched the one on the title he had kept since the theft.
"I'm not trying to sound indelicate, but you're selling my car," Russell told the dealer.
Russell was reunited with his vehicle after police reactivated his stolen car report filed more than four decades ago, the New York Daily News said.
He now plans to restore the car to its original glory.
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