This place has a great selection of about anything you can imagine. Quality? If it was good enough for my plane, I figure it's good enough for my car.
http://www.aircraftspruce.com/
Go through the "Product Index" and look around. You'll be amazed at what you will find under the "Electrical" and "Hardware" tabs.
Here's the section on AN bolts.
http://www.aircraftspruce.com/menus/ha/bolts.html
After knowing about all of this "Right Stuff", you'll never go to the local hardware store again!
Rodger