Nice old spring key keyboards.
The short answer is yes.
Major resale value
Totally as is doa they fetch $10-$20. A set of 25 used good condition springs can fetch the $20 range so that keeps the resale floor nice and high.
Working those can fetch well into the triple and sometimes even
4 digits!
If you have all the key caps and every key has full travel and a strong click, even untested the generic average is in the $50 range.
Beyond that you need to do some work in research of prices.
Ebay is only one source. Check out mercari and offer up and definitely look at
keepaThe most expensive are
The IBM letter series (J and M can get thousands)
The Unicomp keyboards
Digital Equipment
Leading Edge
Altair
Apple
And anything with RS:232. Be it rj9, rj11, rj42 or rj45.
The safest way to sell them is as is, with tested springs. Press each square key cap or hitch (if cap is missing) in the centre, pushing down firmly.
All the square keys should have the same travel, and feel. A firm pressured click at the end. And a quick rebound. If most or all match each other mark it untested good springs and say so; most or all springs.
Ignore and rectangles like space, feed, returns, etc. Touch and sight tests don’t equate to condition.
There’s a healthy market for spring keyboards. Both tilt and buckle springs.
Retro who want the original, gamers who want the feedback guarantee, and fast typers. Anyone typing over 130-140wpm more or less needs one. To slow them down in long sessions where we can out-type the buffer.