Hi Travis and OhioRamm,
I am in the process of building a fowling gun for a fairly small women. It is the 3rd or 4th gun I've built for smaller sized people over the years. Obviously the length of pull will be shorter than usual but keep in mind that drop at the heel of the buttplate often needs to be less in proportion with LOP than you might typically expect for larger people. In other words, you may find that a straighter stock is needed. A 30" barrel, straight or swamped should balance pretty well. In addition, if you go with a skinny barrel (anything under 1") I urge you to use a small Chambers Siler or perhaps his Late Ketland. The reason for the smaller lock is that you will find it easier to shape the lock and wrist area to prevent the gun from looking slab sided. Many guys buy 13/16" barrels and large Silers and unless they mount the lock low, below center of the barrel, there is not sufficient wood above the lock to allow that area to be gracefully curved and blended. Instead the guns have a slab sided shape and the cross section through the lock area looks like a rectangle with the corners rounded rather than a nice oval or spherical shape with 2 flattened sides. Little skinny guns are a challenge.
dave