3" 65's are rather common, locally anyway. For $500 a nice 3" 65 is easily purchased on the internet gun boards as well.

I'd opine that the 3" 686 CS-1 is the rarest of the revolvers you mention, and hence the most valuable. Less than 4000 of those remain extant as near as I can tell.

The 3" 66 being the next in line as far as difficulty to obtain, and more valuable than a 3" 65. No idea how many true 3" barrels were produced, but I would give an educated guess at between 7500 to 9000, comprising the -2, -3, -4, and -5 variants.

Personally, owning examples of all three you mention, I prefer a 3" 66 to them all. Regards 18DAI.