AUA R606 Gas Fireplace Key?

Hey all,

I've had no luck in getting a key that fits my gas fireplace. The ones I've purchased so far do not fit, and Google has been completely unhelpful in finding answers. The key hole looks like this: http://drp.so/43cb1ed20d2e4713a348ec1b38521e87
It seems to have a logo that reads AUA (manufacturer?) with R606 (model number?) next to it. If you peer inside the key hole, it looks like a matching key would have an octagonal base.

Any help would be much appreciated. Thanks!