wave1957,
Perhaps this on-topic
Suburban Rear Window Tech Tip by our own Ken "bartamos" might provide some useful insight on your rubber seal search???
His Tech Tip also refers to this
original conversation on the topic. In there he indicates the
1960-66 Chevy and GMC Suburban fixed rear window gasket is the same as for your 1957 Suburban.
A whole bunch cheaper than the Steele product and maybe helpful for your need. I would note though that the reputation for "Steele" products is pretty much at the top of most everyone's chart for quality and proper design/fit. Many folks will tell you, yup it may be the most expensive, but also the least hassle and best product in the long run.
Your choice on which way you want to go. Let us know how your glass project comes along.
