I'm not 100% sure but according to my reading, an FFL can import a firearm as long as they get ATF Form 6 Part 1 approved, and complete ATF Form 6A, and as long as the firearm is not for resale. In order to do it for resale, it appears that you would need an importer's license as well as your FFL.
From the ATF website:
"May a licensed dealer who does not have an importer’s license make an occasional importation?
Yes. A licensed dealer may make an occasional importation of a firearm for a non-licensee or for the licensee’s personal use (not for resale). The licensee must first submit an ATF Form 6, Part I to ATF for approval. The licensee may then present the approved Form 6 and completed ATF Form 6A to U.S. Customs and Border Protection. Contact the Bureau of ATF, Firearms and Explosives Imports Branch for forms at (304) 616-4550, or download them from the ATF Web page at
http://www.atf.gov/content/library/firearms-forms."
From the ATF website:
"May a licensed dealer who does not have an importer’s license make an occasional importation?
Yes. A licensed dealer may make an occasional importation of a firearm for a non-licensee or for the licensee’s personal use (not for resale). The licensee must first submit an ATF Form 6, Part I to ATF for approval. The licensee may then present the approved Form 6 and completed ATF Form 6A to U.S. Customs and Border Protection. Contact the Bureau of ATF, Firearms and Explosives Imports Branch for forms at (304) 616-4550, or download them from the ATF Web page at
http://www.atf.gov/content/library/firearms-forms."