Got to agree with Darth here. The seller thought he is dealing from a position of strength, because he knows you must have this book! But you're the only legitmate bidder for it, because everybody else in the world says "You've got to be [!@#%^&^] kidding me, a $1000 price for a stupid Man of Steel trade? I don't [!@#%^&^] think so!"
What you should have done is what Darth said - left your bid at $500, and waited to see if it sold. If it didn't meet the reserve, you could have contacted the guy and said "hey, I'm probably the only guy in the world who wants this book, lets trade some stuff that I know you can sell" or, if it did sell to some other slappy, done the same thing. You need to think about jumping in on it with both feet, because you probably could have given the guy more than he wanted in trade.