You have, in the eyes of the law, NO statute of limitation. You are knowingly harboring stolen goods, and in every state in the USA, that constitutes no less than a misdemeanor, and in most a felony. Many states do not distinguish because the value is greater than $500.00, and has been since they went missing.
You, sir, are a felon, according to most states' laws. Knowingly concealing the origin, regardless of it's age, is in most states still a felony level crime. You should contact your states' Attorney Generals' office to get a real understanding of the law. Go to a hotel or some other public place that offers a phone and call, anonymously, and get the real scoop, but in most states, the statutes of limitations don't begin until the crime is recognized to have been reported and serialized.
Removing the badges further accentuates the buyers' guilt in complicity. Just because he recognized the fact they were stolen and he did so makes him complicit in most states. You should surrender them to the authorities in whatever state and allow them to pursue the case. Even if the guy is not well, it matters not, these are doomed to be a sickness to others and you are complicit, knowing what you know, you could be charged as an accomplice after all these years, even though you had no hand in the original crime, just because you are concealing the facts of a Federal crime. How do you like that for bad mojo, ugly juju, mean huhu...whatever.
I know this is hard for you to swallow, "Why should I be the one to lose out" after all these years, but in the eyes of the law, since you know the truth, and the case has never been brought to light, in the courts' view, the statute begins at the time they become aware of the crime, not just the time it occurred. You have some very serious legal issues before you and least of them is complicity to a felony, since train robberies are considered Federal crimes and therefore always felonious.
You should contact a really good attorney and ask, discreetly, what to do about this. Be 100% truthful, if not, you will not get good legal advice. If you truly desire to get to the bottom of this crime and you honestly seek the truth after all these years, you will need to be honest about the whole situation. For all you know, the Feds could still be building this case and you could be the missing link to a huge case. On the other hand, it could be a dead case and you might be in the clear, but I would not take that chance.
We are not being "Holier Than Thou". we are merely stating our positions on stolen goods, the bad vibes they bring to the table when knowingly presented, and the reality of law.
You have been given a pass from us, we judge you not, to this point. It is what you do from this point forward that will tell of your true character. Be a law abiding citizen or an accomplice....the choice is yours, the balls in your court...etc., etc.
If you choose to do the right thing and report this, one of two things will happen: you could be required to surrender the drums or you could be told the crime is past and not to worry. But until you clear this up, those are worthless drums, and carry bad vibes, period.
I have studied law in many states and you are in the drivers' seat, but getting a free pass from those of us that are law abiding citizens, for the most part, is not going to happen.
As my friend Drumhack has pointed out, many of us may well have had "hot gear" pass through our hands. It is what we do with that gear, if we know it is hot, that tells of our true character. Knowingly receiving stolen goods is a crime, in every state.
