Hate to be this guy, but you're probably not gonna have much luck at that price.
Why? Well, I can go to Newegg.com right now, and buy an i5 4670K for $209.99 with free shipping. See the link below:http://www.newegg.com/Product/Product.aspx?Item=N82E16819116899
Same price as yours, but this one is 2 generations newer(uses less power, better performance) and it's from an official retailer so there are no worries of scamming or anything as it comes with a warranty. Not calling you a scammer, but, people don't tend to trust other people online.
I would probably guess it's worth more like $150...? Not really sure, but that seems more reasonable to me than $210.
By the way, how in the world do you have a brand new(I assume it's sealed?) 2500k in 2014 lol? Just curious.
Anyway, just trying to help you out man. GLWS.