Status update...
Ordered (4) spark plugs from an amazon vendor. (1) plug came in. Fighting that.
Mail order wheel bearing came in. Took 4 hours to get in. For those who like drama...
The old steel bearing seized to the aluminum knuckle. Had to pull the knuckle.
I couldn't get the knuckle shimmed up on my press just right, so I hammered the spindle out the middle. By this point I was having a good time hammering and pounded the rest of the bearing out in a number of pieces.
The tie rod end would. not. come. out and its shank quite firmly became part of the steel insert in the knuckle, so the whole shebang came out. A pickle fork eventually got the insert out, but trashed the TRE. Car is immobile while waiting for a mail-order part.
Shoot, let's work on getting the rest of the car ready for inspection. The little 8-inch steel line on the rear axle that goes from the flex-hose to the wheel cylinder was pretty rusty so I go to replace it. The line nuts were quite rust-welded to the line, and I was unable to salvage one of them. Off to the parts store I go. They're 10mm by 1mm. What I was unaware of at the time was that the wheel cylinder (apparently) takes a nut threaded all the way to the tip-- unusual for metric lines. They also take double-flares, not ISO-bubble like expected from Metric.
Dorman sells a 10mm "Toyota" metric line nut with unthreaded portion, which also appears wrong. What's wrong, you ask? There are only 5-6 threads in the cylinder and if you use an extended nut, it grabs about a thread and a half then shears everything off when torqued.

It's fine, though-- I have a new cylinder on order, because the bleeder was stuck anyway.
Did I mention I discovered it'll throw an ABS code (C1344) with the system in limbo? It has "brake line pressure sensors" on every corner and discovered the leak. I need Mini-VCI to clear and bleed the rears-- they have no direct hydraulic connection to the master cylinder-- only the fronts do, in "fail-safe" mode. Luckily I have said software-- When my cylinder comes in I'll see if it works.
tl;dr, it's a rusty mess under there. Googling for how to work 2nd gen prius hydraulics reads, "don't", which is not going to be helpful in the rust belt.