If you want to get more into foods things like avocado could be filling. But if you're talking liquids, it really needs to be BM or formula.
When I discovered I had a lipase issue that ended up causing my daughter to completely reject pumped milk (totally rectified now by scalding after pumping), I had to toss my entire freezer stash. I work outside the home 2 days per week and we do occasional date nights. There were a couple of times when I needed a bottle and didn't have enough stored BM, so I finally broke down and got some high quality organic formula (Bright Beginnings). She rejected it the first time (which secretly made me happy), but drank it right down the next time. Once I got over it I decided it was nice to have it as an occasional option. I would've rather died then give my son (my first child) a drop of formula, but this time around I'm a little more relaxed...I know that I have been breastfeeding from the beginning and will continue well into toddlerhood, so the occasional bottle of organic formula (for an older baby) is no big deal to me.