When I decided my Stingray days were numbered ( only due to their weight, loved them otherwise) I sold off a few. Of course, this was just before s/h ones started to rise in price! Even the USA Subs appear to have done this too, at one time you could get them for around £350, now it’s £500 +.
As mentioned, with the Stingray this probably reflects the recent price hike of newer models. At a dealer near me they have an ex-demo Ray in stock at £1999, so maybe a grand for a tidy s/h one isn’t actually that bad?