Defense Distributed's spokesman and co-founder Cody Wilson holds two of his inspirations Frédéric Bastiat's libertarian classic The Law and his AK-47, which he christened individual mandate. Photograph: Cody Wilson

Prototypes of what would be the world's first fully 3D-printable plastic weapon could go into testing before the end of the year, the organization behind the controversial project has claimed.

"We're ready," said Cody Wilson, a spokesman for Defense Distributed, the company that hopes to manufacture the "Wiki Weapon". "We're sitting on the logistics, time, resources and money. We're just waiting on a little piece of paper."

That little piece of paper is a federal firearms license , the permit that is needed to legally make and manufacture firearms in the United States. Barring an unexpected issue, Wilson expects the license will be granted within the next two or three weeks. Initially, the group planned to create prototypes without a license, but after the media discovered the Wiki Weapon, the group has been under increased scrutiny and several problems have threatened to derail the project.

In September, the group's account on the crowd-source funding site Indiegogo was frozen and almost $2,000 that had been raised was returned to donors. Defense Distributed then managed to secure the startup capital it needed through a direct-deposit platform, Bitcoin, but in October Stratasys, a company from which Defense Distributed was planning to lease a 3D printer with which to print its first prototypes, repossessed its printer.

In response, two Texas companies volunteered their space, to enable the project to do its manufacturing and ballistics testing. Wilson would not provide the names of those companies or the business that is now allowing Defense Distributed to rent its 3D printer.

Those hurdles and the legal grey area in which the project is operating convinced Wilson to take a more conventional approach. In addition to applying for a federal firearms license from the bureau of alcohol, tobacco and firearms (ATF), the structure of Defense Distributed has been reformed. The group, which began as a loose online collective of individuals, now operates as three distinctive arms, all registered with the federal government.