Ahhhh, I love it when people get taken and then attempt to recoup their losses by trying to get their money back out if the next guy.
Pass on them, hit up
http://www.car-part.com and find your own set, delivered to your door for about 1/3 of what this clown is asking. Even if you paid for a new valve job, springs and seals you'll still likely not have much more than about half his asking sunk into the heads and intake.