Right now Sri Lanka is not a place I would be visiting, but that said if you want to get gems faceted there you'd be better going with an introduction. There are some Aussie trained faceting team/s in Sri Lanka but I have no idea how to contact them. They were trained by AFG members so it may be worth contacting the AFG and following through to see if you can get the details before you go.
Outsiders approaching the Gem industry in third world countries is not something one does without introductions and a 'fixer'.
How big are the stones you are looking to get faceted? If the rough will yield stones above 1ct based on an average of 25% yield then consider getting them cut by a Sapphire specialist in Australia as you are more in control of the end result and the potential final value will be much higher.
High value rough can be easily switched by overseas cutters and there are plenty of reasons why cuts can fail, cracks, inclusions, stress fractures etc can appear during cutting and you will never know as the process proceeds.
