For $5, why not try one from The Source
? You'll just need a short piece of coax to connect to wherever you put this in line. Of course you'll also need a copper wire to make the ground connection.
I grounded my Rogers coax right at the demarcation as i had access to the house ground of my fuse panel right there. That is about 50 feet of coax (and a few splitters) away from where I was getting my ground loop hum when my PVR was connected into the HT.
Also I recall somebody mentioned once when this topic was discussed before that you could try calling the provider and ask them to come change/improve the ground of their cable into your house.