2005 Prius, Sporadic high-pitched whining sound

I've got a sporadic high-pitched whine coming from what sounds like the front suspension area. By high pitched I mean at the edges of human hearing. My wife usually can't hear it. It happens when the car has been sitting a while, but the frequency has been increasing lately. It only happens when the car is moving, and only when the car is moving slowly (I've never heard it over about 25 mph, mostly in parking lots). I am like 99% certain it isn't the brakes (debris caught against a rotor has caused similar noises for me in other cars)

I'm pretty sure it's wheel bearings, but I'm looking for one more opinion before I go and replace something the car may not need. I mean, I've gotta do some suspension repairs and maintenance sooner or later, but if I can avoid this particular 140 in parts and however many hours I'd like to. (My car spent most of its life in the desert so it shouldn't be as nightmarish as most wheel hub removals.)

Is there anything else that could be causing this noise?

 

Oh yeah, that's happening. I have a rattle that's probably struts but I might as well do most of the other bushings and linkages when I do that. It's not urgent. But this is a sound that is coming from rotation somewhere, and I'd rather not have my wheels catch fire on the highway.

It's 140 for the bearings, the tools I'll have to buy for the other shit I definitely have to do regardless.

This thing needs:
thorough interior cleaning
battery cooler checked
several pieces of weatherstripping
front struts
possibly sway bar bushings
possibly tie rods but they looked good last time I was under there
and one bank of cells is looking pretty suspicious in Dr. Prius

Also it's an oven so I want to paint it white.

And maybe wheel bearings.