Is AC fan blower motor ready to go? Resistor? Something else?

Hi all. I've read several threads and they didn't seem to have the same symptoms.
I have a 2007 Prius and the AC fan has been acting up. Blowing cold, just the speed is screwy.
Here are some of the symptoms I've encountered:
The fan blows as it should when first started, but after hours the volume of air decreases gradually. This is not consistent, as it works perfectly, not matter what speed, for many hours at a time, on some days.
If I put the setting from high to low for a few seconds than back to high or any speed, it works as it should for awhile than slowly decreases.
The volume of air can temporarily increase when I turn hard left, for example, or hit a speed bump. Again, not always.
One day, I shut my car off for about fifteen minutes after driving with AC for about 5 hrs. I turned it back on and the blower would not turn on at all. I took the filter out and spun the squirrel cage by hand, forward and backwards, a few times. I turned on the fan and it worked perfectly fine for several hours after that.

Does this sound like it could simply be the fan itself, on its last legs? or maybe something else?

 

Thanks. I did read your Install write up already and bookmarked it several days ago. I figured I was going to need it soon.
I was worried it might be the controller/resistor thing. Those aren't cheap.
Its tempting to get a $40 knockoff blower, since the OEMs aren't $70 anymore(seems to be in the $120 range now.)
And....if its not too bad to replace.....Hmmm....I don't know what I'll decide yet.
I need this thing to last another 3 weeks or so (fingers crossed). What are my chances? LOL

 

Read some reviews of the knockoffs, and there were several people complaining of an annoying sound. For as much as I run the AC fan, I can't have that. Besides, the local prices at Autozone, Oreillys, etc were in the $80+ range.
Called local Toyota dealer for price. $150+tax!!!

 

Just a follow up. The struggling motor did last the 3 weeks I needed it to last (well, 2 weeks, 6 days, then it died for good.)

I ended up buying the OEM from Toyota dealer on ebay. $119. Just did the work today. The removal was easier than I thought, thanks to edthefox5's write-up and a couple youtube vids. (one thing to add to the write-up: use a flat head screwdriver to release the locking tab when removing the wire plug from the motor assembly.)

I was a little worried about holding the motor up while starting the mounting screws during re-assembly, but it wasn't bad at all. The hardest part was putting the white plastic cover back on. (I knew it was going to be tough, because taking it out was the hardest part during disassembly) Maneuvering the white plastic cover to line up, at the same time, engaging the tube part on the left was really tricky. So tricky in fact, there was a casualty. One of the screw mounts broke right off. (see pic) Well it looks like the white cover is going to be held with only 4 screws then LOL. Everything else went smoothly and I've got A/C again!!!