Amazon.de has audio clips of "Revolution" by The Beatles on the albums listed below. To listen to a clip, click on any album name and you will be taken to a CD product web page with a list of album tracks linked to song clips.
Past Masters Vol. 2 - Beatles - Capitol (EMI Electrola)
The Beatles 1967-1970 - Beatles - Parlophone (EMI Electrola) (2 CDs)