Sounds like you have a Vellichi swing arm off the earlier models where they even had a dry clutch on the 750 engine.
I tried buyng one of those arms for a project a few years ago off Ebay, but was out bid by an Ex DDer with his own Bike Business that thought he knew better.
Might be better trying to sell it to someone doing a TT2 project as some of the ones out there cost a fair bit
http://www.twowheelclassics.co.uk/ca..._Swingarm.html
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