I don't recall seeing the model 64 in a 2" barrel so I'd guess it's not too common.

A blue box is appropriate for stainless steel revolvers.

What dash is it?
Does it have a pinned barrel? If It's a 64 no-dash or dash-1 or dash-2 it should have a pinned barrel.
Pinned barrel deleted at 64-3.
At 64-5 these were shipped in plastic cases and by 64-6 MIM parts were introduced.

Could this by a Model 64 NY-1 (i.e. a New York City Police Model)? It could be if it's DOA (double action only) and the serial number is on the frame below the cylinder window.

In the condition described (98%) and if it has a pinned barrel and an original looking, numbers-matching box then it sounds like a very good deal.

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Scoundrel & Ne'er-Do-Well