Need advice ASAP/Told is New 226, but???

This is my first post here and I hope I don't sound like an idiot. Anyway, I have been looking to buy a Sig and today went to a gunshow nearby and purchased a P226. Here's the story I hope someone will be able to tell me something quickly before they close up tomorrow the 25th.
Too make a long story short. I see a 226 with price tag on it of $680, looks good, looks new, and ask guy if this is a new pistol and he says yes. I ask if that is the best price, he tells me he will take 630, comes with box papers, 2 15rd mags. I ask again if it is new, says yes. I come back later and decide to buy it. I ask yet again if this is new, I notice the box is not hard plastic, but regular old Sig box, kind of beat up, but I figure it got that way taking it from show to show. As he is filling out papers and talking about price I say "new in box" and he repeats NIB. I get home and do some checking and notice mark is KC, which, if I am correct means manufactured in 1992. In looking at manual I see where warranty card, I suppose, has been removed. So what is the deal? It looks new, but 15 years old certainly is not new to me. Would someone please give me some advice? Thanks

I would take it back tomorrow. Sitting on the shelf a few years is 1 thing. That is another...

without seeing the gun in person it will be difficult to say new or used so Ill just say this, if it hasnt been fired (except testing at the factory)it is still considered to be NIB. even if it was 50 years old.

That is true. But given U don't have have a registration card.... And, U bought it at a gun show, I'd go back tomorrow. U can't call Sig until Monday to find out if the gun has been registered. And then U are stuck, unless the guy U bought from is local.

does it have the tac assessory rail?

I hope I'm not too late. But in this case, I'd use my trusted theory: when in doubt, bail out! Take it back. You'll always have a doubt in your mind.

Thanks for all your thoughts. I was unable to make it back to the show until later and the guy had already left. Anyway, I honestly believe this pistol has not been fired except for the test firing. As I said it came in the original box, with manual along with the test target. It does not have a scratch on it, nothing to make me think it has been used. I field stripped it and it appears perfect on the inside. Called and talked to Sig on Monday and was told it had not been sent back to be refurbished or to be a CPO. I checked it over pretty darn well and everything seems to be fine, the slide has no waggle to it. Knowledgeable firearms people I have shown it to see nothing to indicate it has been used. Thanks and anymore thoughts would be appreciated.

Sounds like things worked out for you. Relax and enjoy your new toy.

I just wanted to point out that assuming the law is similar everywhere you do not have to have the warranty registration card and send it in for the warranty to be valid.