Subs do not come with a cable. You have to provide your own. You need a standard RCA to RCA cable. But it should be a decent one. I was using a standard audio cable at one time, and I had a serious hum problem, I assumed this was from running it beside the subs AC cable. I replaced it with a sub cable from Blue Jeans Cable
. Problem solved.
I suspect a Dayton sub cable from PartsExpress
or one from a nearby Radio Shack ( but NOT a Monster brand - overpriced) would do just as well. Just be sure to get one th proper length with a little slack so you don't put a strain on the connectors.
I assume you meant hook up the sub to the receiver. You have the "sub output" marked in purple (#24), on the diagram to which you provided a link, on page 6 of this thread.