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The CS-HD may last they are for hardened carbon steel
Need to look in Aus for some I think to trial
The yanabida came up real nice Os

the CS-HD polishing stones for hardened steel may be a great option also, the kits are cheap enough 1/8" x 1/2" x 6" of each size
or single stones go up to 1" x 1" x 6" bit more expensive but
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