The five new names added to the original squad are Pathum Nissanka, Minod Bhanuka, Ashen Bandara, Lakshan Sandakan and Ramesh Mendis.
Meanwhile, Lahiru Madushanka, who was previously named in the T20WC mix, will not travel with the team as he is recovering from an injury.
Twenty-one-year-old off-spinner Theekshana, who made his T20I debut in the first match against South Africa and dismissed Heinrich Klaasen, has been included.
The youngster was also impressive in his ODI debut earlier this week, picking up a four-wicket haul.
Sri Lanka have also named four reserves who will travel with the squad as injury cover – Lahiru Kumara, Binura Fernando, Akila Dananjaya and Pulina Tharanga. (ICC)