Safari HP has a bunch of NTO pieces of glass. I'm not sure if the shipping would be a deal breaker. You can also have a local shop cut you a piece and install it. $100-$200 installed is a fair price reusing your old gasket.
I just had a local auto glass shop cut and install it. Don't remember how much, but I did use a new rubber. Give it to them a few days early so the can stretch it over the glass and let it relax a bit. IMHO not worth trying to install yourself.
Keep the gasket wet with soapy water and wrap the rope around the glass 1.5x. Have a second person hold the glass in place while working the rope. I successfully did 2 windshields this year. Kind of a pain but I couldn't find a shop that would do heated glasd
RIP 1994 D90 #999 (engine fire 2002). We'll miss you.