Hi
You can use active USB extension cables (repeaters) to connect distant cameras to the PC. These particular cables serve us well:
MonoPrice 32 feetTRENDnet 39 feetYou can connect several extension cables to each other to cover the required distance. However, I don't recommend to have the total cable length to an individual camera more than 50 feet. Greater length can lead to noticeable latency in data or frame drops.
Also, note that it may be hard to make recordings when you can't supervise a mocap scene and a recording PC at the same time. You may consider using a laptop just for recording, if you already have one. Any decent laptop should be capable of handling 4 PS Eye cameras. You can use an USB 2.0 hub to extend the number of USB ports if needed.