Hmmm, thinking out loud here.
410's (and I would assume 411's as well, although I could be wrong as I don't have a 411 parts manual) run the exact same front drum brakes as the SP310 fairlady. Same part numbers, the lot. I have a full set of 410 wheel cylinders (all 6 of them
) to use on my SP310 fairlady and they are identical to the existing ones on the fairlady.
The SP311 / SR311 fairlady's run a disc front end using Dunlop calipers, and can be upgraded easily with minor mods using Volvo 4 spot calipers (google will fill in the details). You can also buy a kit to put 300ZX 4 pot calipers on a 311 fairlady (google "Spriso Motorsports").
So, it comes down to whether the 310 and 311 fairlady front ends are same / similar enough that brake upgrades for the 311 fairlady will work on the slightly earlier 310 fairlady. And there, I can't help (well, I could, but I'd have to dismantle my 310 and 311 fairlady's and see if the brakes swap over). Perhaps try some of the fairlady forums (311s.org, for example) and see if anyone can confirm ? Or else, find an upgrade for a SP310 fairlady and it should work on a 410 / 411.
Another option (but I would imagine not easy to find) is the front disc setup off a 411 SSS (although perhaps they are just fairlady brakes, the 411 SSS did use the fairlady engine / gearbox).
For rears, pretty sure they use the same drum as your run-of-the-mill Datsun 1600 (again, fairlady's do, and 410 / 411's use similar brakes to a fairlady) so an R31 upgrade should be do-able, although you will probably have to work out how to modify the caliper mounting bracket yourself.
I was lucky to find a set of cheap NOS 410 brake wheel cylinders to use on my fairlady - to buy NOS SP310 fairlady ones you're looking at upwards of $500 just for the cylinders
, so a brake upgrade will save you money as well as make it stop better.
All just theories, but maybe a reasonable place to start ?