Hmmmmm, so guess that RHD Fairlady on Craigslist at $ 38.5k last week was a decent buy after all then.
I was sticking to HS30-prefixed (L24-engined, RHD) '71 through '73 cars with the intention of direct comparison to UK (AUS, NZ) market cars. The car you mention was an S30-prefixed 'Fairlady Z-L' (L20A-engined, RHD) model, so perhaps
less of a direct comparison.
However, the '69 through '73 Japanese market S30-prefixed cars are pretty similar to L24-engined RHD Export market models in most respects, and if you intend to up-engine or otherwise modify then they make an excellent starting point. The trouble is that - in Japan - they are not very far behind their L24-engined siblings in terms of market value...
At some point we will all realise that there is a premium for original RHD '69 through '73 cars and that the very best of them (already do, and will probably continue to) change hands for figures far north of equivalent LHD models. That puts well-executed (proper parts, properly used) LHD to RHD conversions not that far behind original RHD in value, and well up there in terms of desirability when other criteria (lack of rust in unibody structure and components etc) are taken into account. Good RHD-specific donor parts are also a finite resource.
In my opinion, a private builder outsourcing the work as a Project Manager would find it very difficult to duplicate the spec of this MZR car for less money than the asking price...