A guess, educated or not, on value in the current market on any manual Autavia seems a bit like a stab in the dark frankly. I saw one of these go for more than $5000AUD recently, which to me really shows how impossible it is to gauge now as the 7763c, particularly the later red accent variant like this, was, not so very long ago, the ultimate good value manual Autavia. A nice one could be found for just a few hundred dollars, ah those were the days....and it seems like only yesterday.
If it were me I would pass on this watch at the price it has already reached and it will most likely just keep going higher. While it does appear original, the serial number is very close indeed to my own similar 7763c, I personally would struggle with the bezel and marked dial for what the watch is going to cost. That aside these red accented compressors are among my most favourite Heuers and the later 2446c remains my ultimate grail watch.
tony