Welcome on the Forum Robert

If it's a one row it's easy to determine the key.
If the bass side gives a C on the push and a G on the pull, than there's a big chance that it's a C-box

The tuning is a bigger problem.
Is it Cajun Tuning(dry) or not (wet)
When it's wet, than you hear some differences(floating?) in the sound.
I don't know how to explain that in English

There are also keyboard lay-out on the internet to see what note is playing on which button.See link#2

Hope this helps a little.