Short answer, yes, it's a "pu'er" from Hunan.
From my limited understanding, dark tea is to pu'er as oolong is to tiekuanyin.
Basically, there are a bunch of varieties of brick teas that go through actual fermentation, even though pu'er has the most visibility. Although many people say "pu'er" to refer to all fermented brick teas, it technically refers only to dark tea from Yunnan that uses leaves from the large-leafed Chinese tea variety. So a dark tea from Hunan isn't officially a pu'er, although it shares many similarities.
You might have more luck asking in the pu'er forum, as they seem to know a lot more about this sort of thing. Here
's a poorly-worded English history of Hunan brick tea, basically suggesting that early Chinese exporters thought that Hunan brick tea tasted better with clotted cream (öröm), so it might be a better choice for export to the Mongolians, who had a habit of drinking it that way.