You might be suprised that some of those 50 year old parts are still as good as new.
i have a few issues with the suspension "kits;" If youve got it torn apart and dont want to do stuff twice its nice to have all at once but it could be rebuilt from the top down in stages; springs and UCA in a step then LCA sway bar etc in others if you need to piece meal it for cost and drive in between steps (i purposely do this to appreciate each upgrade)
Speaking of upgrades those "kits" usually rule that out, the springs and sway bar are almost no additional cost to get "better than new/original." The same way that some replacements like UCA/LCA can have wild prices(&catchy names) compared to more generic brands yet be identicle in performance. (Think Moog or McQuay-Norris on the shelf at you local parts store) They are not rare and unique parts, simply service replacements.
As for brakes, they are a bling item these days as much as anything, like Gucci you pay for the name as much as the utility. If you want them to peek out from behind your wheels its one thing you might appreciate but it doesnt take a whole heck of a lot to stop our cars. The 11.3" disc is the same size as '67+ I think.