Second clown portrait - need help identifying the right Buchanan

Hello friends!

I once again need your help with identifying the artist. I have two clown portraits (odd, I know) by two different artists and two dilemmas. Posting as two separate threads.
This one is truly intriguing. The signature looks *exactly* like Stuart Buchanan's. So I wrote to him asking if this was his - it is not (sadly), but he said that it definitely looks like his signature and he would have thought it was his if he didn't know better. So the mystery is who is the right Buchanan? Anyone has any ideas? I have also promised Stuart Buchanan to keep him updated on the investigation.
Thank you!