I see you're really looking to buy a chip. But I want you to know you have Much better options I think...
First, you can buy a Generic chip, already programmed for your particular trucks configuration, Brand New and Warrantied, for $250 ->
TS Performance Switchable 6 Position Chip - 7.3L Powerstroke
An even better option, because it would come with more choices and better programming, would be from PHP for an additional $45 ($295)
Beans is closer to that now too. What's happening is that, as our trucks get older, they're selling less of these and dropping prices to get a larger share of the market. I don't know what these guys selling them used are thinking, The want Way too much! A used chip is worth $100 unless it is programmed for your specific application. Then maybe $150...
Just thought you should be making an informed decision

Don't mean to butt-in...