is there any chance of getting data on members of German political parties? In particular the "big ones". Anything starting from lists of Names to more structured data would be a great start. The period of interest would be 1980 to 2000
There are data available from Bundeszentrale für politische Bildung. The pure numbers are probably not copyrightable and therefore Open Data.
EDIT: I answer to the headline. but not to the text. I won't delete my answer for now, altho it does not fulfil the data request stated in the text.