$2.50 per page? That seems a bit over the top. They are your records, so why wouldn't you be able to pull them yourself?
Can you not, as a matter of customer service, pull copies of statements, view them and print them for a customer? Or pull copies of checks, view them and print them for a customer?
My first thought is that you need a new processor if you are "stuck" in this kind of situation.
Along with what John said, I've had great success contacting the requesting party and explaining that I have a TON of information to give them (500 pages on one account seems excessive) and ask if I can narrow that down a bit. Generally, they have about 2 accounts that they are looking for and only a few months in each. Of course, each case is different.
Good luck.