Hi Stephan, great watch and very clean! Because your case is a beaded case, the crown looks correct for this case. One interesting note I did observe is the lug holes with the beaded case, something I don't believe I have not seen before. Very interesting indeed. The ones I have seen before with lug holes were on a polished case and in that case, I agree with Nicolas that it should have a small crown.
Here's a past post I have made on a 3/6/9/12 from the original owner. The was was untouched and as you can see it came with the same crown on a beaded case.
blancpain.watchprosite.com
Best,
Jon