It has nothing to do with copyright.
It has nothing to do with historical correctness.
It has nothing to do with personal feelings.

Computer games are not authorized as culture / art here in germany.
Therefore it´s illegal to use "symbols of unconstitutional organisations".

http://en.wikipedia.org/wiki/Strafgesetzbuch_%C2%A7_86a

Conclusion: If it´s really important for you, then ask a lawyer.
Nobody can (and should) give you an advise here.