Somewhat of a predicament

Yes, I figured out how to get the title to work.

So, this is my predicament. I have a fire safe box that I keep all our important papers in. I have our past tax returns, marriage license, social security cards, birth certificates, all that good stuff in that box. Last week I decided it was time to get our taxes done. I grab my keys to get unlock the safe and low and behold, they are not on my keyring. I don't know how they disappeared, but they did. I have torn this house apart, interrogated the kids and Jeff. They couldn't have fallen off, they are on a regular round ring that you have to pry apart. Yes, I needed the papers in that box for last years tax returns and Zack's social security number. Thankfully, I found our state taxes (not in the box) so I was able to get the information I needed off of that, and I found Zack's social security number off one of his old medical cards. Now, here is my problem......I can't get into the box. Do I pry it open and ruin the box, or do I take it to a locksmith and get new keys made and pay a small fortune for their services?

Any suggestions would be great. I feel like no matter what I do it's going to cost me....ahhhh!!