I have re-uploaded a recording with some photographs of Streltsov that I was recently able to obtain.
You can hear Streltsov descending to a low E1 at the close of this remarkable recording. I was recently able to contact some of Streltsov's remaining family and learn a little more information on him.
Leonid Petrovich Streltsov (4.24.1921 - 12.07.1999) was the leading oktavist in the State Academic Russian Choir USSR under A. V. Sveshnikov running in the second half of the twentieth century. Due to the characteristic timbre of his voice, Streltsov is easily recognizable on many classic recordings Sveshnikov choir, most notably the famous 1965 recording of Rachmaninov's All-Night Vigil.
Streltsov was known for his power in the contra octave, and many choristers recall his performances of Rachmaninov's "To Thee We Sing" where he octaved the final E flat. He was a dedicated member of the choir, taking the sacred repertoire especially seriously. In his spare time he enjoyed woodcarving, often making walking sticks and tobacco pipes. Streltsov sang alongside many other famous oktavists including M. Zlatopolksy, A. Ivanov, and A. Lisnevsky.