I just picked up a like new Interarms Mark X 375 originally bought in '83 or '84. It's not the Whitworth Express model but is essentially the same rifle(Zastava). It doesn't have the express sights or barrel swivel stud. It does have the monte carlo wooden stock, double recoil lugs, and non-express single blade adjustable rear sight. Thing is, I've never encountered a Mark X 375 in anything other than the Whitworth Express or the Alaskan model (which came with synthetic stock). Mine being neither, I was curious as to what Mark X species it is (Classic, Viscount, etc.). It is a completely unaltered Zastava factory rifle. If anybody has one of these or knows what particular model of Mark X mine is that info would be appreciated.