the reason they are so hard to find is because they arnt selling them in the uk, there was some sort of problem with the uk distributers (cant spell today sorry)
there probably wont be any new gabbers coming into the uk any time in the foreseable future
so for getting a gabber at the moment theres only really ebay or freecycle ect or to import yourself
as for avoiding a ZZ because they dont have levels, i made levels for a plastic cage using CT shelves and suction cups, i drilled holes in the lip on the shef slightly smaller then the end of the suction cups and shoved them in, they worked wonders
rather then a new cage, have you tried blocking off the places she chews? when i got Karma (from a rescue) she lived in a tank and on moving her into a bar cage she went mad on the bars, but on watching her a few days and almost pulling my hair out, i noticed she only chewed in certain spots, so i rearanged her cage to block off those spots and after a bit of a sulk and trying to get to the spots for a couple of days she gave up