I saw some games on our local buy and sell group and website. There are games that has very low prices but some of them don't have cases, leaflets, cover. So the question is do you care for all those stuff? or are you good with disc + replaced blue case?
I don't normally buy used games, I've always preferred to buy new. In the rare case I've bought used, the games have been in pretty good condition and have worked just fine. They also came with the original case and leaflets.