I had a massive problem finding a blank to fit my SIBA unit. It seems its like the worlds more obscure key or something. I wanted a spare in-case i lost the original.
Any locksmith can take apart your lock and make a key to fit to it in like an hour, but finding the blank in the first place is an issue.
In the end, after much much hassle, we finally found a blank thats not exactly the same pattern, but fits. Its marked HD IF6.
Once you know what blank fits, its just a simple 10 or 15 pound job for a locksmith to make it fit the lock.