Quick search leads me to believe it's a 6239. Not sure about the value, but that's not what he's looking for. Just a sweep second hand.
"Just", as in I "just" need a new bezel for my Siffert I'll bet.

: One of our friends showed me a watch he bought new in 1970 - a
: Daytona. He just had it serviced and the chrono second hand was
: replaced with an improper hand. The replacement was incorrect
: and fell off when starting the chrono. His watch guy (I hesitate
: to call him a watchmaker) is supposedly trying to find a proper
: hand. I don't know enough to know what is a proper hand for this
: watch. Do any of you know which model this is and/or a source
: for the hand? Thanks in advance.
: Also, he wants to give me a good price for it, but I have a feeling
: this is pretty far out of my range (and it's a little small for
: my tastes).
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