IMO, this coin is legit. Diagnostically, it appears to fit well with pic #4. The coin is kind of banged up. This would result in some post mint damage. I think that's what happened to the upper part of the mm. The V.D.B. does appear to be weak, but also looks genuine.
He also has a 7-day return policy which is always good.
Established in 1981, my wife and I are full-time professional numismatists. We sell largely on eBay but also attend many National and regional coin shows. We also do direct retail sales and even sell coins on approval. If I had to give you three words to describe our business ethics, they would be honesty, integrity and knowledge. Thank you.
But, there have been altered keys that have fooled even the most experienced numismatists. My advice is if your going to buy this coin, buy it already slabbed by a reputable TPG