I only have the Naniwa 12K too. I have found it to be more than enough.

That is because I only touch up on it. I buy razors shave ready or send them for professional honing. The 12K is great for touching up a blade that is already set. It might be cheaper for you to get your razor honed, then stick with what you have. Essentially what Ed has said.

If you want to go to a full honing set up yourself then what Jimmy has said should be a good set up. That said if your edge isn't in too bad shape you might not need to go right down to the 1K.