1829 O.114' R7? Capped Bust Half Dollar PCGS AU55, ex. Link, likely Finest Known

Overton notes cryptically, "Early die states exist without A2 and A3 filled."  Except that, there are truly precious few of them.  In the 35 years I've been collecting, hunting for and studying the Bust half dollar series, I've never found one.  Herrman shows only 4 coins (in 5 transactions) having been sold, dating back to Jan 1994, a period soon to be 28 years.  This is, as far as I can tell, and according to the coin's current owner, Dr. Charles Link, the finest known prime.  The coin is frosty white, with nearly complete cartwheel and just a hint of golden toning.  There is a reasonable bit of prooflike reflectivity, which is something we would almost expect to see on a truly early strike such as this.  For the sub-variiety collector who has (nearly) everything!