Eddie Papczun on a 1946 Indian Chief motorcycle in his store, the Great Republic, in downtown Washington. (J. Lawler Duggan/For The Washington Post)

Eddie Papczun loaded up his newly purchased Mercedes-Benz cargo van and set off to Cleveland for the Republican National Convention with a very American goal: to make money.

“I tell people I’m not going there as a Democrat or a Republican,” said Papczun, owner of the Great Republic, a store in downtown Washington that specializes in U.S. memorabilia. “I’m going there as a capitalist.”

Stowed in the back of his van, and in a rented U-Haul trailer behind that, were historical documents, pre-Civil War flags and 200-year-old oil paintings ­Papczun plans to sell at this week’s convention. They include a copy of the Declaration of Independence printed in 1818 (price tag: $48,500), an autographed manuscript of the “Battle Hymn of the Republic” ($138,500) and a first-edition copy of “The Federalist Papers” ($225,000).

“I really wanted to take items that are, well, kind of sexy and create excitement about the history of the nation,” Papczun said as he drove his van through Indiana last week. “Things that will make people go ‘wow.’ ”

Flags of Valor, a veteran-owned company in Ashburn, Va., will also have a booth at the convention. The flag here, called “Welcome Home,” was created to honor Vietnam veterans. (Chris Coppock/Flags of Valor)

Papczun will have a ­300-square-foot booth at the convention’s Freedom Marketplace, where he and three employees plan to sell collectibles for 17 hours a day — from 8 a.m. to 1 a.m. — Monday to Thursday. This is the first year outside retailers are allowed at the convention. Among the 22 vendors are chocolatiers, furniture-makers, the clothing company Vineyard Vines and Flags of Valor, an Ashburn, Va., company that makes American flags out of wood.

“As soon as we heard about this opportunity, of course we said yes,” said Brian Steorts, 39, an Air Force veteran and owner of Flags of Valor.

Steorts, a registered Republican, says he is not quite sure what to expect from the convention: “We could be busy, or we could be bored,” he said. But he is hoping the event will bring some attention to the company he founded in October. He has five employees, all service-disabled combat veterans, who make and sell flags priced between $99 and $399.

For Papczun, a 55-year-old Air Force veteran, the convention seemed like the perfect place to find new customers. Most of his clients in CityCenterDC and at the Broadmoor resort in Colorado Springs are affluent men — and so, he thought, what better venue than the Republican National Convention?

In addition to high-end memorabilia, Papczun also plans to sell campaign buttons for $20 and cuff links and lapel pins for $50.

“You don’t have to be wealthy to take away something unique from our booth,” he said.

But it certainly helps — especially if you have your eye on a set of documents signed by Thomas Jefferson and James Madison (priced at $17,500) or a 19th-century oil portrait of Abraham Lincoln ($35,000).

Also in Papczun’s arsenal are 18 fountain pens handmade with wood from the original White House by a father-son duo in Bowie, Md. Those will sell for $2,450 apiece.

Papczun took out a special insurance policy to cover his trip to the convention. After all, he said, he is driving valuable American memorabilia across the country — and back.

“This is a crazy new frontier for me,” he said. “We’ll have a captive audience at the convention, but will they want to spend money on this stuff? There’s just no way to know.”