I was in a similar position a few weeks ago .... I had agreed to pay £33,500 GBP for a 348 TS that was advertised at £34,000. We agreed and shook hands on this price, subject to me having the car inspected by an independent Ferrari expert.
After the car had been checked I contacted the vendor to arrange collection only to be told that he had sold it for £34,000 to someone else. I was furious, I had been screwed for the sake of £500 (about $800 USD).
Anyway, I then found the 348 Spider which I have now bought and I'm glad I was "robbed" of the TS. The Spider is much nicer than the TS and the whole saga has now become one of the stories I can tell about how I came to get my first Ferrari.
Things always seem to work out for the best, even though you are left feeling awful at the moment. Don't give up searching, the right car will turn up and you'll be even happier with it.
As for your shares ... well you have to sell sometime and who can predict what's going to happen tomorrow? I sold a load at $29 to pay for my car, they had risen from $25 two weeks earlier. Now they're $35 but never mind, they could have fallen to $15 instead!