Cheers guys. Capt. Vick, the MiG-21L Analog is indeed the Tu-144 wing test bed; Analog was the name the Russians gave it (had to check that; it meant that it was analoguous to the Tu-144). I photographed it on a horrible day at Monino; it was raining and foggy and half of my pics turned out blurry, but I was able to salvage some of them. Three hours wandering around in the rain sheltering under the wings of some very exotic aeroplanes.
Terry, the MiG-21 is at the Udvar Hazy Center in the US; I'm not sure of its history and NASM don't give any such info, just adding that it was displayed at an exhibition of Soviet hardware, so, you're probably right. I know the MiG-15 at that museum is a defector; it's in North Korean markings next to an F-86.