No problem registering them, just have to be 25 years or more old.
November 6 and 7 there will be 20 of them in DC for a celebration of the Twentieth anniversary of the fall of the Berlin wall.
Eric, the owner of seven of them has also sold two of them to the National Spy Museum in DC.
Its common for people to import them, figure out that they really don't want to put up with them and then dump them. You can get them in Germany, Hungary, the Czech Republic and other ex-soviet union countries for next to nothing and then spend $700 to $1200 to ship it here.
The white one here is going to DC for the celebration, two more, including a kombi, are sitting in front of the garage which holds four more.