Hello unfortunately I broke the pane of glass out of my 2500hd crew cab rear window last night. It is the pane behind the back

passenger seat. I spoke to safelite, they only replace the entire rear glass assembly. A local shop said they can replace just the one pane if I can find it (they’ve done it before but customer brought them the pane).

Does anyone know where I can find this single pane instead of buying the entire assembly? I believe the entire assembly part number is 84819603.

Ive looked around on the internet with no luck. Thanks in advance for any advice!