I contacted Mr Drysdale a couple of years ago through one of the Yahoo motorcycle groups.
The prices mentioned for complete V-8 bikes were around $35,000 US.
Its actually not too expensive for a hand built special (considering an OCC 'Kit bike' costs about $70,000)
The 2.6litre V-8 Hayabusa engine costs about $33,000 to import from Britain, its de-rated to 220BHP!!! cant find link at present
(everything is well out of my price range, but I do like engines
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)
PJ