We've had good luck with a Winchester Ranger, Youth model in 20 gauge. It would serve, in a pinch, as a ladies defense gun. Recoil is very manageable and it is probably a little nicer than the Mossberg without breaking the bank.
(ETA: Sorry - this is a pump action as well, though I still recommend it.)
This post was edited on 2/5 at 1:07 pm