Problem with half.com sellers?

[Homura]

I recently purchased a few blu-rays from half.com from various sellers all with ratings of 99.9% or better and over 1000 reviews. Now I purchased two movies from one guy that both claimed brand new excellent condition and one said factory sealed and the other sealed. I didn't think much of it at the time and purchased them (the guy has 1366 positive ratings and 1 negative from over a year ago). I just got them and one was as described brand new factory sealed. The other one however, was sealed, but was in a knockoff case and had fingerprints on the disk. Is this considered how it is claimed? (Brand New*EXCELLENT, SEALED, SHIPS FAST!) I emailed the guy asking for either a refund or a new copy of it in a legit sealed case, but is there really anything that can be done about it?