Hi Zoe, welcome. We do cater to 280zx but members are not as active. Probably because there is less ZX's around now than say 5 years ago.
Your biggest issue will be rust. Since it gets very expensive to repair. But it will be a good learning experience and mechanically these cars are nice to work on (provided not all the bolts are rusty).
And spares are still accessible given the engine's were fitted to many older Datsuns of the era.
Good luck.