Might be Stephanie Walker, but signature looks off.
americanbonsaiceramics.com
If you're on Facebook, there is a page there that does pot ID. Might be worth checking out, although it tends to be more about IDing Japanese makers..
Log into Facebook to start sharing and connecting with your friends, family, and people you know.
www.facebook.com
There are also several Western bonsai potters' ID pages as well:
americanbonsaiceramics.com
Bringing the bonsai ceramics community together and making bonsai pottery easily accessible. Discover bonsai potters of all skill levels, from amateur to professional, in all populated regions. You...
www.arbonsaiart.com