A general store in Judicar.
Its unassuming manager is Kelnor Trisen.
If you know the secret phrase, he will lead you to a sending stone to reach certain people. Each phrase links to one person. Additionally there is a fee associated with using the sending stones. A different fee is applied depending on who you are reaching. This “side business” is not very well known, but enough know it to make it a open secret. Unfortunately/Fortunately, just facilitating communication is not illegal and there is not much the guards can do.