Headlight Clips source
Call Larry Granback at Motor Pro sales, in Midlothian, VA. Their number is 800-468-5700 and you want part number C468. You'll get a box of 25 at $20.63 (keep in mind this was in 2007, the price might've changed) plus shipping. They don't have an internet ordering system, but Larry's a nice guy. They'll get there in about 2-3 days.
Thanks to hawkeye18 at SHOForum.
These clips can also be had from Clips and Fasteners. http://www.clipsandfasteners.com/Headlight_Component_Pivot_Retaining_Clip_p/a15940.htm
Part number a15940. $12.81/box of 25 as of early 2010.