Where to find used computer case parts?

After a week of searching, I have decided that there are no rack-mount cases for Compaq Presario 5200-series computers. Heck, there aren't any aftermarket cases of any kind!

So, I have this Presario case with the front plastic missing. Where can I find either the plastic front assembly, or a complete case? Ebay had none, and well, Compaq wants a fortune for the pieces. What I need is the one from around 1999 or so, with the "Creativity Action Center" in the bottom. And the door at the top.

I need it for a Presario 5240, but the case on my 5280 looks exactly the same. I think all of the 5200's are the same, except some don't have the door at the bottom. Anyone know where I should look?

Yea, I know they are Compaqs, but they are next to free and great for the kids.