Vipola,
Sorry to hear about the low life fu*ks that stole your crest
. Keep an eye out for it, I'll bet it's around someones neck hanging from a chain.
The good news, by the looks of your pictures, is once you replace the crest and rubber gasket you won't be able to tell it was stolen, except for the "C" note missing out of your wallet.
The nuts that attach the crest to the hood are stamped out. What I mean is they have no threads, just two sharp edges that cut their own threads into the blank stud's of the crest shanks. The photos show corrosion on the studs. With the paint scratched under the crest already I would suggest a thin bladed screwdriver with a cloth under shank so you don't scratch the hood and basically jam it under the heads of the pins. Then try and unscrew the nuts with a socket because this will cause the nuts to force their way back off the shank. This sounds harsh but if you try and drill it out the shank will just spin with the drill bit unless you can hold the shank.
Good luck bro.