Springbank Single Malt Scotch Whisky
Springbank Scotch currently exports their full range to the US (and have done so for many years) as well as to Alberta in Canada so it is certainly available in North America.
As for whether the bottles you bought are truly limited, you would really need to send more info about them. Take some photos and post them here on the Whisky.com Forum. Be sure to get really great, clear shots of the label, the bottle, age statemenet, etc.