What are some good ugg style boots for my mom's Christmas present?

ok, so one of the presents that my mom has decided she wants this year is a pair of ugg style boots. I really don't know where to start. i've seen them from $15 [walmart] to the $140 original uggs, and even some that cost more. she dosn't want the original ones though, because she dosn't want that much money spent on one pair of boots for her. honestly,i would like to keep the price under like $50. and preferably, the short ones, not the taller boots, as thats what she asked for. i've looked at a bunch of different places, but i've just become slightly overwhelmed and at this point i'm not quite sure what to get her. can anyone help me out and suggest some boots? thank you so much!!!