This 450x seems to tick the boxes.
https://www.ebay.co.uk/itm/115229198343?hash=item1ad4320807:g:-mIAAOSwFEhh6B3O
Nice if you want a dirtbike - will cost a couple of grand in wheels, suspension and brakes to make it a motard though.
Would still be a hoot to ride on trailwings though - I can confirm I ran out of brakes before I ran out of grip with them on the street.
@Airhead started
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This 450x seems to tick the boxes.
https://www.ebay.co.uk/itm/115229198343?hash=item1ad4320807:g:-mIAAOSwFEhh6B3O