Look up a shop in Glendale called LTS Mastertech and talk to Mike at the shop. He is the one who got all those exact cables and a brand new mic for me for $150. Just did this install.
Hey if you get a chance I am still having problems with my mic not working in my set up (see my thread for details) and the only way to trouble shoot it is to find another 2007 NAV unit and try plugging it in to my system so I know if the problem is in my wiring or the NAV unit itself. Any chance, since you live in LA, that I could get you to let me try plugging your unit in my car to test. In exchange I can help you out on your install with wiring diagrams, troubleshooting, etc. What ever it takes to make it worth your time let me know. This would seriously solve a 4.5 month long problem.