@Cheryl_M if those packs fit you well, they can accommodate 15-20lbs (depending a little on the bulk of what you're carrying to get to that weight).
For the original member, having a hydration system included was important so all of the packs we suggested include the hydration bladder - is that also important to you? If not, there are other packs you might consider for rucking. Further, the packs we suggested above will be men's/unisex sizing and will have similar options using a women's specific fit:
We hope this helps; let us know if you have additional questions!