Premmie’s bottle transition

Hi mummies. I gave birth to a premmie 3 months ago, he was on the slowest flow pigeon bottle that only holds up to 100ml (provided by hospital) His feedings now has increased to 120ml, i’m in a process of finding the right bottle for him to prevent overflowing. Tried avent newborn 0m bottle but its always overflowing. Any mummies who experienced this, what brands are recommended? TIA!