Hawk brake pads - worth it?
I think in your case I would try a tad smaller diameter MC first if you have enough pedaltravel left currently.
Can't go much smaller than a 15/16" bore. I don't think there is an off the shelf aluminum MC in 7/8" for our cars but don't quote me on that. Cass does not carry them, neither does Mark Williams. I have read about people using the FWD ones but I don't think they fit without modification, I believe the mounts are different. I don't want to deal with putting a new master in either. I hate brake fluid.
I tried an adjustable push rod but to get more leverage it put the brake pedal too high up off the floor which was weird and unsafe. It's good where it is now with the original rod. I think it's likely just the size of the caliper pistons, (45mm) they probably don't generate enough clamping force.
So again, rather than throwing expensive parts at this situation (calipers), brake pads are probably the easiest and cheapest step to take for (potentially) better bite into the rotor.
And again, if the pads fail to hold the car, clearly the problem is elsewhere, namely the caliper pistons. If that's the case, I'm probably looking at that minimum offset Wilwood kit for 10" drum spindles or an Aerospace Components set for original KH brakes. Both of those are around $800 so I'm not really looking forward to that day since I already spent a pretty penny on the current setup.