Balsa USA carries what you are looking for.
http://shop.balsausa.com/category_s/141.htm
The stuff shown on this page is very high quality and reliable if your cables are to be used for structural or controls. There are cheaper ways to make cabling, but not as easy and worry-free as this.
As I said in an earlier post, you can probably find a wire rope supplier that can provide these products locally and maybe a little cheaper.