this is one of those tricky ones that i think you'd have to adapt to adapt to get where youd want to go with it.

The connector looks like Reg Green Blue Ground (black) and Sync (white), i'd take a DMM to it to test to make sure and see what the voltages are across your RGB lines.
after a quick search it looks like you might have to to go from that CGA to a VGA connector (pin it your self more likely) and then adapt from that VGA to your component. you should be able to test the VGA directly on a computer monitor as long as it isnt picky and wants both horizontal and vertical sync

This is just off the top of my head though.

Most monitors/tv's have VGA connectors on them, why wouldnt you go that route?
nearly directly in, less potential loss of image quality