Here it is; Maria Yudina performing Mozart's Piano Concertos. 20 and 23 to be precise.
http://www59.zippyshare.com/v/94891464/file.html
There is some history to the recording of the 20th, evidently Stalin heard it over a broadcast and loved it so much that he requested that he get the recording himself. Since it was a broadcast, they would have to do it all over again. So Soviet authorities dragged Yudina out of her bed in the dead of the night, by surprise, and summoned an Orchestra to the recording studio to accompany her. All the authorities were in the studio, including Stalin himself. Everyone is completely on edge and you can feel the tension in this reading of the music, there isn't anything else quite like it. Apparently when Stalin first heard Yudina's keyboard he broke into tears right there.