Seal between the vent window glass and the frame

I started tearing about my doors to prepare for the seals when I decided to separate the vent window frame from the glass. The seal was dry rotted plus i want to powdercoat the metal. Does anyone know what I can use between the glass and frame when I put it back together?
It's also the same stuff between the glass and channel at the bottom of the rear window.

Should I just go to a glass shop?

got mine from an auto glass shop: 1/16" X 1.5" X 3' roll

Thanks Carl, I actually just found that out today. It's called butyl tape and they said they would have it in the next couple days.
I was curious about the price of a new windshield so I asked for them to check for me.
I couldn't believe when they said $150, I think I might order one since mine is chipped.