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talk to him about shipping options, he has fast shipping ones, also while at it grab a set of naguras, they are very useful stones at very nice prices.

There are places that sell tomonaguras, I got my best one so far from Maksim
JapaneseNaturalStones

Mejiro and then tomonagura should work fine.

Depends on which is harder, if the tomonagura is harder than the base stone then you will be honing on mainly slurry from the base stone.
If the base...