I found an NOS rear view mirror mount for my '66 convertible on ebay. Paid $125 for it. It's a 1 year, convertible b-body only item.
Think I was looking at that and hemmed and hawed. Good score. Think it was the same guy that advertised a pair of "used" 66 headlight bezels but thought they were new. Got those, they were mint except 2 light 1/8 lines on lower half.
Or...an original Nichols Engineering NASCAR 426 hemi single 4bbl cowl air intake. It's not going on the car as we cut the firewall to accept a real NASCAR race used air intake but it's ~2" off in one direction so if anyone's interested it could be for sale
Gray Rock brake lining vintage decals/stickers for the Petty build. A guy was selling the decals in their original envelope (from the 60's) with a letter from the company thanking him for his interest in their product and request for the decals.
I like to look for adds for other cars that are similar to mine and might use the same parts.
Mislabeled or the seller doesn't know exactly what he has, can get you a good deal also. They're out there!