(CNN) -- Dave Taylor, a Civil War antiques dealer in Sylvania, Ohio, was excited about the possibility of buying a "top-notch," genuine .36-caliber Spiller & Burr revolver that had belonged to a Confederate officer from North Carolina.
A Tennessee woman who inherited the revolver from her late father sent him photos and, eventually, they agreed to a price, he said.
"The purchase price we discussed was significant ... about double the annual salary I earned my first year out of college in 1979," Taylor told CNN Tuesday in an e-mail. "But the gun appeared to be in stellar condition, and I was anxious to buy it."
A day before driving down to Knoxville to finish the deal in late November, Taylor said he thumbed through an old reference book that indicated a photo of the sidearm was courtesy of the Museum of the Confederacy in Richmond, Virginia.
Taylor contacted Catherine Wright, collections manager at the museum, and by comparing photos and the piece's serial number, they determined the revolver was a match with one stolen from the museum in 1975.
Now, thanks to the intrepid research and the Tennessee woman's interest in doing the right thing, the gun should be back in the museum by February 1, the museum said Tuesday.
The revolver belonged to George Washington Rains, known with older sibling, Gabriel, as one of the "Bomb Brothers" for creating all manner of gunpowder-infused weapons for the Confederacy during the Civil War
Rains, who early in his career did a stint on the faculty of the U.S. Military Academy, survived the war and lived into his 80s, dying in 1898.
The North Carolina officer's military trappings, including the prized revolver, were housed in the Museum of the Confederacy.
In 1975, the revolver, worth an estimated $50,000 today, was stolen.
According to the FBI office in Knoxville, Krissy Evans had a Civil War revolver that was in her late father's belongings and she decided to seek an appraisal.
After "substantial research" and learning the weapon's history, Evans immediately decided to return the artifact to the museum, the FBI said in a news release.
The six-round revolver was not Confederate standard issue. Instead, individuals would purchase such a sidearm.
This particular Spiller & Burr gun was one of about 1,450 made, probably in Macon, Georgia, said Wright, who contacted the FBI.
"It was not terribly common," she told CNN.
Taylor said he considered the piece a "topnotch" version of that revolver.
Wright, who has kept a short list of items stolen from the museum, said she got a call December 1 from Taylor, who forwarded photos for the comparison.
"There was a nick on the wooden handle that was exactly in the same place" as museum photos of the revolver, according to Wright.
Taylor "was very instrumental" in the return of the gun, she said.
The museum does not know who stole the item, although it doesn't believe it was an inside job, Wright said.
Items were being transferred in 1975 from the original museum building to a new one when the revolver disappeared.
"It was more of a rickety old case" the pilferer managed to open, she said. Guards apparently were very trusting of people moving the artifacts, she said.
CNN left messages Tuesday for Evans, who Taylor believes had no idea the item was stolen.
"Ms. Evans is to be commended for her ethical integrity," Knoxville FBI Special Agent in Charge Richard L. Lambert said in the release. "By returning this artifact to the museum, Ms. Evans has ensured that it will be preserved and treasured for generations to come."
Jason Pack, a special agent with the FBI in Washington, said there was no formal investigation. "We are just a facilitator" in the revolver being returned to the museum.
For his part, Taylor is pleased he didn't spend a "small fortune" on the gun, only to lose it.
"There's no glory in having a piece of history that was stolen," he said.