I could be taking this out of context, but it sounds like you only want to breed him because he is purebred and beautiful. That is not a legitimate reason to breed, and if he has a floppy ear he should not be bred. And unfortunately, price does not determine quality.
Every dog you see walking down the shelter row was once thought to be "the best dog ever" or "the most beautiful dog ever" too. What does your dog offer that those dogs do not? Something to keep in mind.
Neither of the contracts for my dogs came with anything about the ear, but rather had specific instructions to contact them if one didn't go up, since steps can be taken to help it go up. However, it is genetic and a fault, and lets face it, the ears are a huge part of this breed that we love so much.
But like said below, that is not the make it or break it. If your dog is titled and has proven that he has multiple, more important reasons why he should be bred, than maybe he should be. However, if the only reason is that he is beautiful, he shouldn't.
I would personally be upset if I purchased a puppy, the ear didn't go up, and then I later found out the parent had a weak ear and was bred regardless. But that's just me. It's one thing if I damaged it, but if it was knowingly passed on I feel that I would be a little angry. (This is hypothetical of course, I always want to see the parents first
Just enjoy him as a wonderful pet that he probably is. Always buy a puppy first and foremost as a companion and whatever other plans you'd like, deciding on breeding should always be decided after the dog develops.