If its only had a couple boxes run through it then $450 is fair in the Georgia/north Florida region. If there are any extras with it, it is definitely fair. If you can get it for $425 or less it is a really good deal.
If you are the one selling it then the same applies. You can give a fair deal or really good deal. If you were trying to trade with a shop then you'd be lucky to get $400-425 for it because they are in it for profit.