Those should be standard industrial panel switches and indicators. The first thing you need to do is determine the mounting hole size (30.5mm, 22.5mm and 16mm are the most common currently, older equipment may differ). Then determine the number of positions and poles needed for your wiring. Once you know that, look in industrial control catalogs for compatible devices. It's not unusual for the switches to be sold/configured in a modular way where you order the switch banks separately from the knob/actuator.
Lots of makers (e.g., Allen-Bradley, Schneider, Siemens, Omega, IDEC) and lots of distributors (Automation Direct, Mouser, Allied Electronics).