Non-gas shocks will be available at Nissan, and designed just for the 210. Better quality than all those gas shocks, which are designed for multiple cars.
Nissan
* 56210-H8926 ABSORBER KIT-SHOCK REAR B310 $71.67
An alternative is Koni adjustables, you can turn them for soft, medium and firm.
In america, everyone cuts the coil springs - just don't cut much. No more than 1/2 coil, and then see how it sits. In Australia for some reason it is illegal to cut the springs, probably because the government regulates personal work, you can't even swap engines without hiring an Engineer to review the work.
If you want to go with custom springs, call
Quickor down in Portland. They aren't listed in the catalog, but they will make a set to match your specifications.