The ones for the rear bumper are in good shape the front leave some to be desired. $30 plus shipping from Wyoming.
I just looked on the Buick Farm and they have the fronts (7 of them) and a left rear. I still haven't been able to find the parts here. I hope this helps.
Looks like this is all I can find. I thought I had all of them but not looking good. I am still looking.