This is a subject near and dear to my heart:
I agreee w/ HDBRBuilder:
"A few years ago, one could go into a pawn shop and pick up a tube item for a song...but since then these shops have discovered computers(for the most part) and with that have discovered eBay...and they pretty much KNOW what the "good stuff" in tube equipment is going for lately...so when they get it in and somebody defaults on payment...it ends up on eBay pretty quickly"
I went to a local pawn shop (SF Bay area) owned by a friend of a friend looking for tube gear: the pawn shop
owner told me outright he directed all tube gear to a local vintage audio dealer and got top dollar for it.
This guy could even rattle off some of the classic gear model #s, even though he was no audio buff.
OTH, I think thrift stores, especially non-Goodwill thrift stores, have that needle-in-a-haystack potential:
A friend of mine who owns two pair of Klipschhorns told me she saw a pair of Klipsch speakers with built-in tube amps (excuse my ignorance of the Klipsch line here, but do these sound like production models, or custom?) at a St. Vincent dePaul store in San Jose a while back: asking price: $100.
Sadly I heard about these long after the fact, but still it does show the possibilities.
eBay has all but swallowed up the good deals in stereo gear anymore, but it does still happen.
As to Goodwill, I don't know how they operate nationwide, but here in San Jose, I've known at least one former Goodwill employee who told me he had tube amps he bought up as they came into the Goodwill he
worked at (the timeline here would be over ten years ago), and there was a major scandal in San Jose several years ago about Goodwill managers selling premium donations out the back door to corrupt dealers.
From my personal experience (too long to go into here), I have reason to believe high-end audio was on the dealers' shopping lists.
On another note, I have a restored Dynaco ST-70 which I have waffled about selling for some time.
If you are interested M00n, drop me an email and I can give you details