I was unable to find any when I redid the air dams after having the car painted. So, I made the springy washers by hand out of 0.008" stainless shim stock on hand. The original washers were at least 0.010" thick so if I were buying, I would get 0.010" to 0.012" stock. Just used some aircraft shears to cut out the circles. I also replaced the original, severely rusted special screw hardware with stainless bolts and nuts. I found a stainless nut that was thinner than a normal nut and about the same thickness as the nut built into middle of the special screw post original one. I dropped the bolt thru the hole in the bumper from above, added the thin nut and tightened it up. Next the air dam and the 'fancy' new springy washers. Then I used a stainless locknut to hold the assembly all together. Got all the stainless bolts and nuts at Ace Hardware. Lots of work but at least it won't rust again. I HATE RUST!