2007 Silverado Door Problems

[dermz28]

I got a NNBS 07 Silverado, and well yesterday I was opening the drives side door from the inside and I heard something snap in the door and now the door will not open from the inside, I can still open the door from the outside. I been searching for the problem and it seem there is a cable that runs from the inside door handle to the door latch. I called the dealer looking for the part, I was told I need a whole new lock assb. since they dont sell the cable, gave me price around $150 just for the part. This can't be right, others have said that they just replaced the cable, but I cant seem to find the part number for the cable, so I'm looking for a little help here finding the part number