Thanks, John!
I ended up going the "get-it-now" route, and these will be here at my house sometime today:
https://www.amazon.com/330uF-1...ndustrial&sr=1-5
I will give an update on how I fare with this salvage project. Best case, I get the switcher running again; worst case, I have enough replacement caps to proactively swap out all of the Wincaps in my extensive PS2-5V fleet before powering any more of those engines up!