If you have good travel history, getting a visa to any asian countries shoudn't be a problem. Singapore and Maldives are visa free for Sri lankan citizens. Sri lankans can go to few countries without visa ( u can google those countries). You can get visa to Thailand and Malaysia within few days if you provide all the required documents. They might call you for an interview if they need any clarification or will issue the visa without intetview. I think Canada is the hardest country in the world to get a tourist visa.