The end note for this post
The block of four stamp in the story is the Small One Dollar Red Revenue Surcharge that commonly referred to as Small Red $1. There is only one block of four, which regards as the Holy Grail of Chinese stamp, and 30 odd singles in the world. One of the singletons was auctioned off December 2004 in Hong Kong by a Swiss auction house, fetched an astounding US$410,256, set a record high for a single Chinese stamp in history. The block of four is still with the same owner since 1982 – it was a bequest of the owner who purchased from Chow that it could only be sold to a Chinese. Apparently his widow diligently obliged. There is one Philatelist, Robert Chin, in San Francisco who enthusiastically told me that he had gone to the bank vault to view the Holy Grail few times when the previous owner was still alive. When this block of four showed in Beijing during the international stamp shows, government would always place 2 army soldiers with riffles guarding it!
In 2009, it changed hand again. Reportedly the new owner paid US$10+ million.