I've seen so many fakes of the higher Orders that I would require some rock-solid provenance ( and by this I mean a handshake with the actual person it was awarded to, or their close family, and an interview ) to plunk down $60,000. If this couldn't be arranged, I would run, not walk, away from the deal. I don't know about you guys, but I've seen more fake Ushakov's than real ones.
It could be authenticated by McDaniel, Sotheby's, Christies, etc. etc..I trust no one when it comes to something of such value. Of course I would have another set of eyes take a look at it AFTER I had been satisfied that the individual and their historical relevance to the award were authentic.
Before 1976, all awards were considered "property of the State" and had to be returned to the State upon the death of the reciepient with the exception of the Orders of the GReat Patriotic War which were allowed to be keep be the family. After 1976 the law changed and the family could keep all of the awards. (When you see large groups with only OGPWs left, this is usually a sign that the person died before 1976. I have even see an Order Book where the family wrote which awards were returned and when.)
As for the awards being "stolen" this is a tricky question as well. If you are talking about pre-1976 items where they came from the archives, someone usually sold them. Since that someone usually worked for the State, it would be fairly embarrising for the State to pursue this avenue. Although I'm sure you could "show" that they were stolen at one point.
When you talk about awards being stolen from a family, in many cases, but not all, the family will sell the medals and report them stolen to cover their rear-ends. In the early days of collecting, it was common to find peices with family altered serial numbers (they would add a 1 or something) hoping to avoid any possible trace back to them.
In the end, I think this comes back to a case of government embarrisment over anything else. After all, the only reason the people were selling/stealing the awards was because of the utter collapse of the Russian state and its inability to take care of the basic responsibilities of Government. I think that the natural economic forces will correct much of the "flight" of these awards and collectors and private organizations will bring them back to Russia by buying them overseas as it becomes profitable to do so.