No easy map that I know of!
bvandedr,
Information correct as of last summer:
France no problem mode C only.
Netherlands:
Not allowed to use mode C at all (though in practice ATC do ask you to turn it on).
Without mode S, you must remain not above 1200ft and outside any controlled/restricted airspace and outside the Amsterdam North Sea Area (basically everywhere more than 1/2 mile off the coast).
Belgium:
Must remain outside controlled/restricted/militiary airspace without mode S.
I hope that's of help.
Unfortunately in this regard Europe is not one country, and each country has different rules.