If that's the case then what you have is just the stock 73+ BBP disks with a set of tubular UCA's. Your stock lower control arms will work just fine with a rebuild, if you're doing that then you can add a boxing plate to the bottom of the stock LCA which you can also use to correct any wear or play that has developed in the LCA. Jim Lusk has a nice video on that...
I actually prefer manual brakes on these cars, with a 15/16" master cylinder you get a very nice brake feel without being too heavy or too overboosted. If you still want to go power, DoctorDiff has a nice Bendix reproduction booster available. It's not the cheapest, but it is a high quality booster that looks correct for the application. Bendix Style Dual Diaphragm Booster for Mopars
He also sells the reproductions of the original combination valve, which should work fine for you since you're running the stock front and rear BBP brakes. Mopar 1 Piece Proportioning Valve
There are cheaper ways to get it done, but brakes aren't something you want to cheap out on. And since you have mostly factory reproduction parts so far, keeping with factory reproduction parts will mean they should all work well together.
HEY BLU , WHAYT ARE THE CHEAPER WAYS U MENTIONED / What is the best set up to run w/ coil over springs , using a stock k-frame .
Am running 4 wheel discs already on the car , want to go back to the stock kframe w/o torsion bars .