I'd have to say my HP-2000 systems that are running are the rarest that I'm aware of. I know of a few folks who have various bits and pieces towards assembling one, but not complete. I know two collectors who (each) have most if not all of the parts, but the systems are far from operational and likely never will be.
So I fairly strongly suspect that my running HP-2000's are the only ones left, anywhere. I have one HP-2000/Access system using dual 2100A/S cpus with HP paper tape readers and punches, another HP-2000/Access system using dual 21MX/E's, and an HP-2000/E using one 21MX. Each of those have their own 7900, 7906 disc drives and 7970 (not the 2000/E) tape units. I think the most I ever paid for a system at once was $1500 for a "system", and about $2000 for a pallet of two incomplete systems. But in order to get the 3 HP-2000 systems mentioned above and running, I'm sure it's edged uncomfortably into the 5 digit range. All the other systems in my collection, while perhaps highly sought after... there are tens if not hundreds of identical systems in other collectors hands. J
