I don't know the answer to you question - but I have one suggestion - Enfamil, which we used, also sells premixed formula in 4 oz glass jars - take off lid - slap on nipple - and you're ready to go. We bought a case or two of these on a cruise when we took our 8 week old. (and brought along some rice cereal to mix in the last bottle of the day). Enfamil shipped the cases to the hotel where we stayed the night before the cruise left. We did carry them on ourselves (heavy!) but feared breakage if the porters took them. You may want to do a combination - I don't know if any other brand of formula does this and our baby just used the standard kind of Enfamil formula -
There are a variety of Enfamil packaging - you can also buy little individual packets - for example, to take with you if you go on an excursion off the boat.