I know what you're saying, but playing devil's advocate for a moment: He makes a big point about how he got this set from the owner of an old time RCA dealer so apparently he feels that the provenance alone makes it worth a ton of moolah.
Am in the car biz, and get people who literally GIVE me running cars quite often. This has skewed my "value system" concerning what I'm willing to pay for cars. Am thinking the same may hold true to those is the vintage TV hobby too.
Am NOT crtitcising you or anyone else in the least, just an observation---and am certainly not saying what the seller wants is reasonable or not. Just trying to put a larger perspective on things.
We all know in our heart of hearts the time is probably coming when a lot of these sets will go up in value.....and only the collectors that had been playing early or those with deep pockets will be in the hobby (look at Lionel trains).
Eh, but what do I know?

Am just a meckanic
Anthony