Have you checked the MOST standard for automotive optical bus systems. They're using POF (plastic optical fibers). Because that system is designed for automotive means there are automotive compliant connectors available.
But in general you should check other things fist. Maybe you did but just in case. Some things that comes in my mind: What type of fibers are required (POF, single- or multimode fibres). What type of optical cables will survive your environment (vibrations, strain, chemical, temperatures, ...). How much space is available (especially if you need strain relief). How much space is there for the connector to be fixed. Is there any electrical connection running along with the fiber (I've seen MOST connectors mixed optical/electrical)? Is mating/unmating in rough environment required (that will probably will be a huge problem, esp. if you use multi- or even single mode fibers)? Having a pigtail (short piece of fibers with a connector) coming out of your box an option?
Maybe this alone will rule out some solutions are make the search for a solution easier/harder.