Comment by CamperBob2

It does look a little newer than the oldest examples I've seen photos of, but it's hard to say what the range of possible production dates would have been. You might be able to find a date code on an electrolytic capacitor or some other internal component.

There are a few HP 200As listed on eBay in the $100-$300 range. Not sure if they're actually selling for that, though.