In all my years as a mechanic I always unhooked the e-brale linkage from the cable on that style, and removed the whole assembly from the backinplate as shown in your last picture - then reassebled with whatever new parts were required. Check the cyls closely to make sure nothing is sticking. Back off the handbrake cabke adjuster so it doies not screw up the service brake adjustment, and after everything is re-assembled and adjusted at the wheel end, look after the handbrake adjustment/adjuster. Mage REAL sure the cabkes azre not hanging up ANYWHERE or you will end up repkacing shoes again After 20 years it would not surprise me at all if you need cyls and cables, but it IS a Toyota and they are pretty high quality, dependable vehicles. (Iwas a Toyota service manager for 10years)
Adjuster looks good, but clean and lube
The cable MUST move easily and smoothly. Same with the cyl pistons. be carefull not to pop them out but they should both push in easily and you should be able to slide the pair of pistons easily back and forth in the bore.