Grab some used R33 Brembos, nice quality rotors and some punchy pads. Fingers crossed you can sell your current gear to a Silvia owner, but you will still be looking at around 3k total
So would suggest you grab some NISMO brake ducts or similar which bolt to the castor rods, some good fluid, pads and tyres. If you are stressing that sort of brake setup then you probably shoudl be slowing down because of brake fade
Try some Castrol SRF brake fluid, i am loving the Endless CCX pads i run and just do a walk around the cars current brakes. Check caliper pistons move freely and rotor condition. Binding pistons cause pad drag on the rotor which all throws heat into the brakes
If you find your calipers are in need of a strip and rebuild, the rotors are shagged, then its time you look at the dollars you have to spend because you may be able to justify a slightly bigger spend for a nice 4 pot upgrade using an AP, Alcon or Brembo caliper with a 332mm rotor. So what is the budget? I love spending peoples money on brakes