Well........
I believe that that hub is a copy of the Shimano 110 hub. But I don't know if the dimensions are really exactly the same.
I don't think there'll even be a brand name. It's more likely that Pacific Bicycle merely contracted with someone else, perhaps more than one supplier, to supply hubs that meet certain specs.
Your best bet would be to put a caliper on that in order to get a precise hub diameter measurement.
Then you'll be able to order your sprocket adapter with confidence.