This stuff is actually a polished aluminum. It should be available from your dealer. I seem to recall it is about $80-100 per piece (two per windshield).
I bought a new set for my front and found used set for my rear. I was told it would be destroyed when being removed. This is not true, once the glass is out it can be safely removed with ease. I now have a front set in good condition and a rear set in good condition with the exception of one nick (which I think could be rubbed out from the back side with patience). My are from a 71/72 and they should be the same, if you are interested in them send me a PM.
Coupeguy is absolutely right about the process, the glass must come out. The gaskets are also available from the dealer, around $90 for the front at least. Who ever installs it must be familiar with roping-in techniques. The coupe actually has a triple seal gasket which is beyond painful to get in place. I had a pro do mine and it took him 4 attempts and 4 cans of glass gasket lube to get it.
If you take your glass out you should also consider that this is an opportune time for the real coupe masochist to change the headliner. I had an "upholstery artist" lined up to do mine and he backed out at the last minute. I wound up doing it myself with material from World Upholstery. It came out OK but only because I spent two full weekends and had a large supply of weatherstrip adhesive and binder clips. I have a sunroof car which, I believe, make this job less difficult. Since it has a hardboard (cardboard) roof panel to glue to you do not need to sew hanger loops in every 10-12 inches. The moving sunroof section can actually be done separately; it is possible to remove it through the top.
