Found in this wonderful guide to 420 free movies that you can watch online, Strike is a early communist propaganda movie by the director Sergei Eisenstein. His another well-known propaganda movie is The Battleship Potemkin and is also now in public domain. Both of them are silent movies and many bands has composed soundtrack later. He employed unique movie editing techniques that can be still seen in the movies nowadays.
One of the soundtracks available for the Strike movie was composed by Alloy Orchestra. Unfortunately, it is not available anywhere online and Alloy Orchestra sells it only as full DVD including the movie.
I hope Alloy Orchestra will soon publish the full quality music (FLAC or MP3 320 kbps) of theirs on Bandcamp (or Amazon at least), so we can buy it online without requiring their fans to buy a DVD you will never watch.