It appears that “Stompie” is indeed Russian-made but belonged to the Czech army and took part in the suppression of Prague Spring uprising of 1968.
Following the end of Communism and the dissolution of Czechoslovakia, it was decommissioned, sold off and utilized in England as a prop in the making of the 1995 film Richard III. On completion of the film, it was bought by a Bermondsey resident in South London as a present for his son!
The man had previously failed to secure planning permission from the local authority to redevelop a vacant plot of land that he owned and so, in an act of protest, he placed the tank on the site with its gun turret turned towards the council offices.
Stompie is now regularly repainted in a wide variety of colour schemes, often by some of the best graffiti artists in London.