Here's an 'alternative' version of Rival Tribal Revel Rebel by Crass. This was released on a flexi disc in 1980 and the download is in FLAC format.
DOWNLOAD RIVAL TRIBAL REVEL REBEL (FLEXI VERSION)
Note: If the above link doesn't work try the following...
(megaupload links seem to download faster than mediafire)
RIVAL TRIBAL REVEL REBEL (FLEXI VERSION) [MEGAUPLOAD]