The old Recon 1s have a different lock, and the handle shape is totally different to the new ones. The scales won't be interchangeable. Ordering one of the new Recon 1s will be a lot easier than trying to get scales that look like the new ones but fit one of the old models.
Besides using the Tri-Ad lock, the new models don't have steel liners which makes them a lot lighter. The pocket clip is also better. I'm not a huge fan of the new handle shape for utility purposes, it has a kind of guard that keeps my hand too far from the blade (probably a plus if SD is part of your needs).
Cold Steel serrations aren't the best, and I've seen plenty of their knives with damaged serrations (usually the tips of the smaller "teeth"). They were all used rather hard, though. I only have one serrated Cold Steel knife that I bough more for the novelty factor than anything else (a Vaquero Grande). I've used it on thick rope, bottles, cardboard and food, so far it's held up OK.