The only way to get access to their entire set of online practice material is through their course. I doubt Kaplan has more than 10,000 questions. Especially considering that some of their practice material has duplicate passages. For instance, some of the passages on their later tests used passages in the topicals and q-bank. Then of course there's Kaplan's verbal which makes up some of those questions and those aren't that good. That said, Kaplan does provide plenty of solid science practice passages.
Let's take a look at TPRH's Workbooks:
For each passages there's about 7 questions
Verbal Workbook: 43 passages and 4 Practice Tests
43 passages with ~7 questions + 4 practice tests x 40 questions = 461
Science Workbook:
-Physics: 425 discrete, 62 Passages
859 questions
-Gen Chem: 92 discrete, 93 Passages
743 questions
-Biology: 146 discrete, 87 Passages
755 questions
-Organic: 138 discrete, 45 Passages
453 questions
3271 questions
Then there are BR's science books which contain around 3300 questions. I'm not including their verbal because it's not good.
What I'm getting at here is that you don't need to spend $1750 to have plenty of practice passages.
