But for the purest engine experience, displacement has no replacement. All other methods are simply attempts to artificially recreate the benefits of displacement.
If you want to import one then go for the "R" model
They only made 100 or so. They're rare as the proverbial rocking horse poop and will cost you a bomb.
Oh dear... head's needs to be extracted out of the rear panel methinks. Of course the had to update the interior eventually - it's logical. They'll only rust here because they're built for a country that doesn't need to grit their roads every winter.