Do you already have the transmission you're using for the swap? On my 2nd donor transmission (from LKQ), the bracket and a cut cable came with the transmission.
The PN I found for the cable when I was researching a ways back was 68507315AA - you could try that one. Are you going to attempt to route it to the stock location? Russell suggested just mounting it somewhere under the hood and fabricating a bracket to hold the end, no need to route it inside the cab. I currently don't have anything installed and can crawl under the vehicle with a large pry bar and pop it into neutral if needed but always planned to go back and buy the 68507315AA cable and just mount it under the hood somewhere. As far as cables go I would think if you're not picky about the pull end configuration, you could try searching for the cable from a different model and mount it under the hood.
As for the bracket, I MAY have a spare if the transmission in the truck has the bracket installed already. I know my spare has a bracket but I may need it if the currently installed transmission doesn't have it.