The Sinhala translation of Harry Potter looks to have come about in 2004, with books 1-5 being published by Sarasavi Publishers (Pvt) Ltd. Book 6 wouldn't be published until 2011 and book 7 in 2012. The books are increasingly becoming harder to find in the secondary US markets. Additionally, I have been scammed by Sri Lanka book sellers, taking my money and then never sending any books, so be careful!