I guess I should have said "new used crest". I'm not even sure if they can be found new...didn't even look.
I got it from Woody. It came from a car that had been in an accident with airbags deployed, so he just cut off the flap with the crest on it and sent it to me. After removing the rest of the old flap, I was able to slide the retaining washer down the post to get better acces to the flattened tip in order to squeeze it back into round.
I did this by carefully heating up just the tip with a small butane torch and squeezing it little by little with a pair of pliers. Once round, I could then slide the washer off.
To remove the old crest, I just used a Dremel to cut off the flattened end. Put the replacement crest in, washer on, then re-flattened the exposed end of the post. To protect the new crest, I laid 2 thick pieces of leather down, placed the airbag cover on them face down and slowly flattened the post (rivet) down with many moderate taps with a small hammer.
Getting the cover off the airbag requires removal of the airbag.
Disconnect the battery and wait a few minutes with the ignition in acc position to ensure all power is out of the system. Remove airbag (T30 Torx). Remove charge (4 x 10mm hex) and place in a safe location away from metal and other possible sources of static, then it's safe to remove the cover.