The bare strut is the same for the 1200 coupe & the 120Y [Aust built cars from July '76 excepted] & so are the disc brakes. Springs too if i'm not mistaken, so these parts will provide you with a stock upgrade, but use the 1200's upper spring seat [the bit that bolts to the body] to avoid raising the front.
The 1200's dual circuit master cylinder has the same specs for both drum- drum & disc- drum cars, but you should remove the residual pressure check valve from the front brake circuit of the cylinder [the rear part of the cylinder] or alternately splash out & get a new disc brake one.
Datsun also used a smaller bore rear wheel cylinder on the disc brake cars & these are available new at rediculously low prices [under $20] so I would recomend that you get, & fit, a pair of these too in order to avoid embarrasing rear wheel lockup in the wet.

Pedal pressures are higher in a stock disc brake car & this might be the last straw for well used original cylinders, so plan ahead.

This would be regarded as an entry level upgrade, but if you are running a stockish engine & don't do stupid things, it should be just fine.

Talk to Neil [Dattoman_1000] as he is the resident brake specialist in your area & he will give you the good oil on rotor availability, component selection, & he is also very helpfull to club members on parts pricing.