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Any tomo that works on your hone will be fine, doesn't have to be Nakayama at all, you can use many different tomos, they will all give you different results.

Asano Mikawa Nagura progression is just one way to get there.
Some like to use a Diamond Nagura, then they get a quite course slurry, way courser than Koma, and they let it break down.
You can also...

I wouldn't care too much about getting a Koma, it sure would be fun to have but I don't feel it's necessary.
In my honing or straight razors and kamisoris on Jnats I want to remove all scratches...