I'm assuming that if he is a Durrer champion he isn't a puppy any more, am I right? I am also thinking he is neutered. Regardless, I think that is reasonable for a Durrer champion and I would pay it. I also love Durrers - nice faces and gorgeous coats on the ones I've seen. How old is this guy? Good luck with whatever you decide to do.
I have a 3 lb female, 7 months, and she is very, very healthy in every way. Knock wood!!