I will first start off by saying that in my opinion, you have purchased a rare coin at a great price. Without seeing the coin in hand, i would have to imagine that the spots certainly did have an effect on PCGS grading the coin a 67. May i suggest that you resubmit the coin to NCS, which can remove the spots, and sit back and enjoy the new holder your coin comes back graded in.... $2200 is a no brainer, the spots, the best thing that could have happed to you considering you bought what you thought to be a lower grade coin due to hairlines etc. You purchased a coin graded long before the recent chinese coin boom and not sent to NCS conservation. I hate to say it, but it seems at least in the chinese coin market, the expert grading company or Superior at the moment, is NGC. Which of course presents buying opportunities to buy good deals like this one. Good Luck!
Pengyou