[Accelo]

I know the one without the lip came from Brothers.
The one with the lip was likely from ccr_products off of Ebay.
Search; 67-72 Chevy C/K Truck LH & RH Side View Door Mirror Arm Rubber Gaskets Pair.
$7.95 and free shipping.

And yes, I liked the lipped ones the best. Enough that I changed out the old ones to the lip style.
However, to be fair the flat gaskets protected the paint, just fine, as they were large enough to cover the edges.
Interesting fact is Classic Parts allows you to view your online orders for only a short time. I wish they just left the order history on there site.