I trust filestube for downloads, so here is page: http://www.filestube.com/search.html?q=Stara+Basn&select=All
They are likely all active and good quality. Also, like Jelen posted, I am sure there is many torrent sites.
I have original DVD though, so I have never had to look online, but try those links.

BTW I have never heard even of that Russian movie. It looks great! Old Slavic movies rule!!!