Alpine Safe missing innermost door key...HELP!

Greetings all. I recently purchased an Alpine Safe. I have the combination and the key that openes the 'first' inner door. But I do not have the key that opens the door on the small compartment above the drawer. I tried to use the key that I have...but it doesn't seem to be the right key for the small door. Any ideas where/how I can get a key for this door? I found a couple of lots of old keys on eBay...is it worth trying that? As a last resort...can I just drill the lock out? Any and all help will be appreciated! Thanks!