My division of AmerisourceBergen carries a sterile opth betadine in 30ml. Maybe you could give them a call to see if you could order it for your facility.
We make the betadine opth solution for OR. We use sterile BSS in 10ml dropper bottles and make it our selves. Kind of a pain, but the don't use a whole lot.
The only problem with making the betadine opth solution yourself is that the dropper bottles are not sterile. That was an issue that came up here. Our sterile processing department would have to sterilzed all of the bottle and droppers for us, etc etc and it was not an acceptable answer for our administration.
Sterilized product doesn't seem to be much of an issue with these doctors, since they now carry one 30-mL bottle from room to room and use it an multiple patients!