STOCKHOLM — Helmers Mans Marlind and Bjorn Stein are reteaming on Swedish thriller “Ballastexistensen,” due to start production in spring.The 35 million kroner ($5.2 million) pic is a co-production from Sweden’s Breidablick, Denmark’s Nimbus and Norway’s Torden Film with a German production company also expected to board the project. Producer Karl Fredrik Ulfung said the script was out for casting in Hollywood where Mans and Bjorn are repped by CAA. If any American stars are interested in the project, Ulfing expects the pic’s budget to rise. Ulfung would not disclose the plot, but added: “This story could take place anywhere. Right now we are scouting locations.” Marlind and Stein’s first feature, sci-fi thriller “Storm,” was a local hit that sold to 30 countries.