16s are tough to find...i looked for years to find mine. If ebay doesn't have any all you can do is throw up some want ads on all the forums and craigslist and keep an eye out. When i finally got mine i had just about gave up, and they practically fell in my lap.
Just throwing this out there, maybe you can expand your options and look for Lincoln Mark VII wheels also.
They're 5 lug but all you'll need are Mark VII rotors in the front and Ranger drums and axles in the rear. Then paint them black and you're in the game.