So I took the DAT in 2009 and I remember the RC passages from that. I took the GRE a few weeks ago and if you're looking for similar questions and materials those passages/questions will help you.
FYI though GRE passages range in subject matter (literature, history, culture, science, etc.) much more than DAT passages. Though GRE passages are just as boring and difficult to read as DAT passages. The reason I bring this up is you can rent a GRE book from your library for free.