Mary Lou Acothley 1940s
I found this picture in collection of historical photos of Arizona. The note regarding the picture indicates that it was taken on the day of a contest she was competing in. I believe the contest maybe either riding or shooting although I cannot say for sure. The costume is very American Southwest and that dazzling smile and pretty eyes make her a winner no matter what the contest.
If you follow the citation link below you can browse the collections they offer. However, many of the pictures are watermarked.
http://azmemory.lib.az.us/u?/otmind,15