Hello if you do not mind co2 one of the best options I have found was a modified Crosman 2240. My daughters are grown now but when they were young it was very hard finding a gun that would fit as well as having a trigger that would not destroy accuracy. With the 2240 you can put a stock on it and cut it to fit(many options from factory, TKO22, or an AR adapter) also use slip on moderator with a front sight (giving you the ability to use irons and a little bit more barrel length as not to sweep herself). I had 2 2240's the first was a stock gun with the rear receiver plug removed drilled and a paintball ar stock added with a TKO22 moderator, the second was a Mountain Airguns modified 2240 with a TKO22 stock and their moderator with a front sight pin. My daughter will still plink with the Mountain Air 2240 from time to time and I recently just passed the other 2240 to a coworker for his daughter. If you do not like co2 you can use a Crosman 1322 very similar but pump up instead. Both guns are very light, good beginner triggers, easy to modify, and accurate as a converted carbine. Also I say 22 cal as they are easier to load. Well this is just my experience I hope this helps Eric.