Gibbons said that the price was the highest ever paid for a single Indian philatelic item.
A set of 1948 stamps picturing Mahatma Gandhi has sold for a record 5,00,000 pound (approximately Rs 4.14 crore, as on Wednesday). The "Service" tag printed on the stamps signified that they were for Indian government use and increases their rarity.
The company said the strip of four 1948 Gandhi 10 rupee Purple-Brown and Lake "SERVICE" stamps is considered the most important and desirable item of post-1947 Indian philately, with only single examples otherwise recorded in private hands.
The Queen owns another strip of four in her Royal Philatelic Collection, the world's largest, most valuable private stamp collection.
Stanley Gibbons sold one of these singles for £160,000 to a client in Uruguay past year.
One sheet of 50 stamps remains intact in the Delhi Postal Museum, while only thirteen single examples from the other sheet are authoritatively recorded, including the strip of four just sold.
"Given Stanley Gibbons' specific expertise, we are best placed to identify, authenticate and trade rare Indian stamps of the highest quality".
"The recent sale follows that of another Indian philatelic rarity, the famous Four Annas, which sold in March this year for nearly 110,000 pounds", the statement said.