Just get good quality standard spec disks. I wouldn't bother with grooved/drilled again as they are a bit noisy and the holes block up.
New callipers are not that dear, refurbishing them is possible but a swap is easier.
Brake pipes may well snap off at the ends so budget for replacing some.
Check servo on master cylinder, the body of the servo cracks with flexing and rust, nest to the master cylinder fixing bolts.
Look up trailerfitter vids on YouTube for wheel bearing adjustment, this will help with reassembly and save readjusting them later.