Thanks for your reply. Real OEM doesn't show the cable, my dealer couldn't find it either... But GROM Audio to the rescue!

So Audiovox's customer service was very responsive and tried to help but their technical skills are not so great and they don't have and can't get the cable. Apparently they used to but not any more.

Next I tried PhatNoise but they don't offer the cable separately. They stated that if you damage the cable the only option is to buy a new DSP kit.

I finally found GROM Audio and ordered the cable for $10 + $2 shipping over a 2 minute chat session on their website. It arrived in a couple of days, I installed it last night and all is working well.

THANK YOU GROM. If I had it to do all over again I would buy all their GROM-BT3: Bluetooth Hands Free and Audio Car Kit. Apparently, the coax cable is included free with purchase if you request it. These guys really know what they are doing technically and they really know how to treat a customer. It was clear by their responses to my inquiry.