When you have a legitimate need, management is likely to listen; especially when you can put a cost to how much is attributed in manhours/salary to routinely solving similar "recursive" problems.

I would suggest you discuss having some sort of development area where you could tackle such a task. You have a lot of data, so you probably need a better db engine, but if they aren't willing to give you the tools you need, perhaps you could daisy chain a few JET (MS Access) databases, to have something a little more robust and scalable.