In 38+P
Any of the "majors" stuff above 125 grains.
My preference is for heavier (150-160).
With that barrel length your options are a bit wider. Or if you want to just settle on one and forget it? The 135 Gold Dot Speer seems to be the load of choice. The short barrel version might offer just an ever so slight advantage?
(EDIT)
Sorry, forgot to mention that either you, she, or both of you selected a wonderful little gun!