I would look at a shotgun or a Glock 43: GLOCK 43

The already legendary G43 is a GLOCK Single stack, 9 mm Luger caliber pistol. It is ultra-concealable, accurate and a fantastic tool for all shooters regardless of one’s hand size. The grip has a built-in beaver tail design which allows the shooter to acquire a high and tight grip. The aggressive texture of the grip surface allows for comfortable and reliable operation of the pistol. The large magazine catch makes quick work of removing the six round magazine. Engineered based on the same superlative standards that GLOCK is famous for, the tiny G43 tolerates the same torture tests all its bigger brothers in the GLOCK pistol family withstand.