I was visiting a local(-ish) LGS this morning (great new-to-me LGS find, Clay Shooters Supply). They have an unfired, new 6520 in their shop. Unbelievable! Has some surface barrel rust from storage. Apparently was from a confiscated collection; still had the Dallas PD evidence tag attached to it.

I was going to buy it and tear it apart for the upper, but 1) it's a large pin lower and 2) couldn't bring myself to do that to such a pristine example.
5 years ago, I would have bought it just for the collection, but I'm divesting myself of those kinds of purchases.

Pretty sure its up on GB.

Where’s that at id like to go check it out? Sounds like a cool piece of history. Price probably too high for me or you’d have got it!

Clay Shooters Supply in Dallas. Northwest Highway & Dallas North Tollway.

We still have 6520s at work that were purchased not long after the North Hollywood shootout. Most of them are pretty dinged-up, but I likely have the option of buying one when they get replaced this year or next year.