I looked through the books and didn’t find anything. At some point you have to make some assumptions. Usually when you get a three initials it is a husband and wife. I see the three letters as BKY, could be wrong. The closest thing I come across in hallmark book is BNY for a Bessie Yazzie, but can’t get any results in searching her work. The next thing is the age of your piece, it definitely appears to be pre-world wide web. Sometimes identifying artists from this time period can be tricky.
Thank you for your help.