I know a guy who bought a frame from the U.S., it was for an old Limey bike, maybe a Triumph. He went to the licensing office and explained that he found the frame in a dump with a bunch of other parts and he wanted to resore it. He told them he didn't want to put any money, time or energy into it if he couldn't get it registered. They told him to write a letter and get it notarized. He did that and they gave him the unfit permit. In the letter i think he explained where and when he found it and that he checked with the police to see if it was a stolen motorcycle.
I don't see why the importer can't take the Japanese registration, the bill of sale from the person or company that it was registered to and any shipping papers to the licensing bureau and get the unfit vehicle permit. Does he need the recall letter if it is more than 15 years old?