Look at the VT brake upgrade threads, 1” m/c and dual diaphragm boosters are getting harder to find & by the time you o/haul them you’ve invested more into a poorer preforming brake system than upgrading to the later brake system.
Other than the hubs, VT sets up are very well priced. Use the std rear VB-VS rear disc set up & you have a descent brake that stops you! Just source good pads (depending on your driving style).
In summary you’ll need:
2 front hubs, VT (fast fill) master cylinder, VS plastic booster, VS resivour, VT front calipers, adopters for single flare & dual flare fittings on master cylinder to brake pipes, pair of VT rotors, new front brake hoses. Must refit the strut tower to master cylinder bracket to control flex when applying the brakes!
It transforms the braking system & looks all factory.