I am from Scandinavia, and I am currently living in North-America. I am having problems finding this species of fish, usually referred to as Arctic Char. It is closely related to salmon and trout. Is it farmed in North-America at all?  According to the article, a subspecies is known as blueback trout but was extirpated. Does this species survive in the waters here at all? Can it be bought fresh?  I think this species of fish if referred to under a different name in the US. 
First, it doesn't go by another name in Canada (in English, anyway, it has an Inuktitut name.) I see it regularly on menus and in grocery stores in small Ontario cities. Not a hard fish to find at all. There are also fishing expeditions to catch your own. The Canadian Department of Fisheries and Oceans says:  Arctic char are a highly priced delicacy, marketed mainly fresh and frozen as whole-dressed fish and steaks. A small quantity is also processed into value–added products including smoked char and jerky. Commercial landings were 57 tonnes in 2012 , 52 tonnes in 2011, 29.4 tonnes in 2010 and 31.8 in 2009.  It is also farmed in Canada and the farmed product is considered sustainable. You didn't say what city you're in, but if it's large enough to have a fishmonger I suspect a phone call will be all it takes to find out if some is in stock. If not, call a few grocery stores. 