You can purchase a 9mm brake vacuum hose . The 9mm size is also equivalent to 11/32″. An important specification to look for is compliance with SAE J1403 for brake vacuum hose applications.
This hose is designed for light-duty, power braking applications and meets SAE J1403 standards, making it compliant with LVVTA (Low Volume Vehicle Technical Association) regulations.
Material: Resists heat, oil, grease, abrasion, weathering, and ozone.
Operating Temperature Range: -34°C to 125°C, with intermittent use up to 135°C,