280z 2 seaters are not exactly expensive in the US at the moment, you can still pick them up around $5k in relatively average shape. The cost is in importing them, the fact that they are LHD seems to put the majority of members here off also. Personally it wouldn't bother me all that much..
With a sunroof etc.. it's going to bring the values down.
I'd say worth about $12k registered and on the road, compliance done etc..
Value as always is in the bodywork and lack of rust (fingers crossed).
The Scarab doesn't really appeal to me personally, I think it possibly would to an enthusiast in the US but it was never a Nissan sanctioned thing, rather an aftermarket company modifying a 240z in the way that Shelby took an AC Cobra and stuffed a V8 under the hood. Ok so I guess it's kind of cool, but still not where my interest really lies with these cars.