ChrisW

You're most likely to sell it for a good price here or a facebook group for swords; also people will be more likely to appreciate it properly.

Looks like a tsuba repurposed for your kai gunto or simply put in place of the missing original.

It could have been made by a country smith or perhaps it is more musical in nature than a shakujo? You said the iron plate resonates, yes?

Some kind of Buddhist ritual implement would be my guess? Reminds me of a Buddhist monk's staff a lot.

All I've got is that it is a late Muromachi piece. The hada in the shinogi doesn't suggest Shinto in my eyes, though better photos would make it easier to hazard a guess. Still, congratulations!

As a reference, a good polish by a properly trained togishi runs about $125/inch. Not trying to deter you, but if you're doing this for financial gain then it won't be there. If its sentimental, then that's up to the polisher if they'll take the work.

John is saying that the blade itself is real and antique, but the signature is not done by the purported signee. In nihonto, this is called "gimei," which is fairly common.

Pictures are upside down! Also, never buy from Komonjo as a first buy or eBay for that matter.

It may not even be the remnants of a longer blade, with the quality of the photos, it is hard to tell. Gilles could be correct here.

Grey is a wise guy, take heed of his advice and you won't be disappointed!

Thanks Adam! I'll DM you about it.

Looks like the very much abused remnants of a wakizashi. The geometry is all wrong for the boshi (the tip), so it was likely broken and reformed into what you see now. That being said, its not worth the effort and if you want a complete Japanese blade for a collection then you can do better. I'd save your money and wait for something better! I can't say as to what the kanji means but it is crudely inscribed and probably is nonsense.

If it is on both sides of the blade in the exact same spot starting from the edge upwards, then the chance of it being hagire is drastically higher. But no, these are scratches from cutting something.

A quick google search yielded Massimo Rossi. He is indeed recognized by the NBTHK as a polisher whose work is worthy of being judged. If this is the guy you're referring to, then he seems like he might be your best bet in Europe. I can't say I've seen his work, but he did indeed do the apprenticeship so you should be fine with him if he chooses to take on your piece!

How long is the cutting edge? Not saying this sword is very valuable but it could have potential if a togishi did a window and if the sword could be more or less identified to a certain smith, thus making restoration financially viable. Those are two very big IF's.