Hi yes the seagoing coasters where armed and painted grey in times of war, there was hundreds of them of all shapes and sizes. There was store carriers, oilers, water carriers and ammunition carriers. They were all collectively owned and operated for POST(n) or in other words the Naval store system. In peace time they were unarmed where painted black hulls and buff upperworks. Most were called C plus a number, although the RNAD and the water carriers had names. The officers had uniforms and it operated like a private navy. I have several photos of old coasters of various kinds but this site says it all comes to too much memory to download. If you have any particular type you want let me know and I will see what I can do. The history behind the these boats goes back to the old original dockyards and sailing vessels a very old and honourable history.