I need some advice on getting another stone for touching up the edge on a straight razor. I have a Naniwa 12K stone and would like to get one more lower grit stone from this. There is a Naniwa 5k stone would this be a good next stone. It is expensive so that is why I'm asking. what about the diamond plates.Would like to eventually get into more honing with more experience. Does anyone have any suggestions on this? or advise. Is there another approach for me to take?