I think Murphydog is about spot on in price. It's rare to find a pre-lock with box in excellent condition, and a 10 round cylinder. My 617-1 is only a 6 shot, which I don't mind, and unfortunately it was after they had started using the black rubber Hogue grips. I really liked the older wood combat grips that they used prior.
My 617-4 with 10 shots, 6" barrel was bought in 2019 used for $500 as you see it. I took off the scope and added a proper rear sight. It is a Pre-lock and a wonderful rat killer. Came in a nice case.
I bought this 4 inch model last year for $ 795 without the red dot sight. The grips I bought off of Amazon and they are Korean. The biggest expense is shipping.
I love the feel of the 4 inch over my 6 inch. It just seems to balance better in my hands.
When you get it buy a few DS-10 speed loaders for it. You won't regret it.
As for value, it's in the eye of the beholder I guess, I'd not sell either of mine for anything in 3 digits, they are more valuable to me (and presumably others).
As for 6 shot over 10 shot, for me the only reason for a 10 shot is if I'm shooting a fair amount, otherwise the 6 shot guns are more valuable from a collector standpoint, but who knows.....??