I bought a pair of orvis waders without trying them on (shame on me, but I assumed the booties in a new model were really the same size as in their previous model) when i was headed on a big trip and my waders sprung a leak right before that. the wad of excess neoprene under my toes was very uncomfortable.

a couple of thoughts:

might womens' waders have smaller booties (I haven't checked)

you can get special order booties from some of the wader manufacturers for an extra $50 charge. I am pretty sure simms does this

i do a far amount of cold weather wading so I did as is already suggested. I bought a pair of neoprene socks, and I wear them in conjunction with a pair of heavy wool socks, and they fill my korkers with no extra neoprene lump. it does mean you need to get boots that are large enough to accomodate the extra neoprene layer. if you are going this route, try the combination on to make sure you have a good fit.