Since there's no way to know how a used pistol has been treated and maintained, it would seem a simple and inexpensive precaution to replace the recoil and magazine springs.
The guide rod is of a newer design being used where the plunger is not staked into the rod body under a collar, but is pressed into place into the coil of one end of a spring (which can also be removed from the rod).
Here's a thumbnail of a CS45 guide rod and a 4013TSW guide rod, each made in the new design. You'll notice they each have different plungers, one plastic and one metal, and I've placed similar plungers to one side.
The plastic plungers can become somewhat rough after repeated field-stripping due to the slide stop lever's pin being pushed across them. The metal plungers were released later. The trade off to the metal plungers are that they can sometimes make it a somewhat harder to push the slide stop levers in & out as opposed to the softer plastic plungers. I've tried both and I went back to the plastic plunger in my CS45. I really don't have a preference which plunger is used, though.
Recoil springs for the CS45 are relatively inexpensive, and to make shipping costs worthwhile I finally ordered about a dozen recoil springs each for my CS45 and CS9. I shoot a lot, but not that much with just those two guns.
I just wanted to lay in a supply to last me for a few years.
The guide rods seem pretty durable. An improvement over the older style. I only have one spare rod for the CS45 in my parts supply and none for my CS9. I ordered the one for the CS45 just out of habit one day while ordering some spare parts but have never needed to use it. I ordered a couple of spare plungers just to see the difference between the metal and plastic versions.
As far as finding a NIB CS45 sitting on some dealer's shelf? Who knows?
The CS45 & CS9 are still listed in the LE/Gov catalog because they're still available for production orders, although I've been told that if they have some left over (overruns) in their vault from a prior production run that S&W will allow a S&W LE Distributor to order one for an individual officer (and the distributor can set whatever price they desire). There aren't a lot of authorized LE Distributors (CA only has 2, for example), though, compared to regular commercial sporting dealers.