Let's see, "Good working order" with stickers like "Reject YTO unlock" and "Channel 1 inop", a screen you might be able to read in a dark room?
The funny thing is that the "Reject" sticker was removed after a few pictures.
All this for 939.55. What a deal!
YTO unlock is most often caused by dried/dead capacitors, usually the big ones in the PSU go first, which then kills the tantalum caps everywhere else in the instrument with ripple. So big recapping action, done this and had sucess on a 8566A.
Ref unlock is only because the oven is cold, because the seller powered it up just recently.
Channel 1 inop could be everything, either just a bad 2.5GHz band switch relay in the front end or something bad went on somewhere deeper down in the instrument.
So I would say it's most probably fixable, but not worth the $1000. More likely somewhere in the $500-$800 range.
That TM500/5A22 thingy is much more sinister IMO. Power it up and the magic smoke will be released