Since you said charter it is likely tv cable. Just go to you local home store and get some RG6 cable. 4 ends...and the crimp tool if you are going to use that kind of ends. They make ones you can just screw onto the cable with your hands in many stores. You also need a couple of the barrel connector things to hook everything back together. They show on the packages exactly how to strip the cable back.
Hardest part will likely be crawling around so you can get close to the wire. I would replace as much of it as you easily can in one long piece. From the rodent damage I have seen before they have lots of other places they chewed beside the part that is broken.