I think your asking for a solution for a conduit that's too narrow.
You might be able to use the rapid run system:
http://www.rapidrun.com/
It will let you run one cable and select different end connections. The big drawback is that it's pretty expensive compared to just a regular hdmi cable.
You might also search for hdmi over fiber and hdmi over ethernet (also both very expensive), but I couldn't find a system in which the adaptors were removable from the cable itself (making it bigger than an hdmi connector).