As per the book being published by Dr. Reuben Ramkissoon and Dr. Rajagopalan (Philatelic handbook on Mohandas Karamchand Gandhi - 2006) , only eight copies of the Gandhi 10 Rs Service stamps are known in private collections!!
This stamp is considered to be the rarest gem of the independence issues. Jal Cooper had described the Gandhi 10Rs Service stamp as "practically unobtainable"
Excerpt from an excellent article titled "The Story of Gandhi Stamps by Mr T.N. Mehta".
"Why a 10-rupee Gandhi stamp? Commemorative stamps invariably are issued in popular postage denominations; the 10-rupee variety in the Gandhi series is the solitary example of its kind. This step deprived a large number of collectors of possessing the full set because they could not afford the 10-rupee stamp. To other philatelists this was a boon, as the value has been steadily mounting year after year.
Philatelists the world over were agitated by this inclusion of a high denomination in the Gandhi set. Margaret Bourke-White of Time/Life, who knew the Mahatma well, met with Sir Benegal Rama Rau, the Indian ambassador to washington, and later sent a long cable strongly protesting this move, and stating that it was highly improper for the government of India to issue a 10-rupee stamp in the name of Gandhi, who always used the cheapest form of communication - a postcard."
For sure, Gandhi would be extremely distraught to know of the 10Rs SERVICE stamp's catalogue value !!Expertization certificate from RPSL (1982) and the BPA (2006) . Overprint (SERVICE) blackened-out on image.