I think that most of the onliune vendors carry the replacements for these.

I have done this it isn't really all that hard. They will just pull off and
the new ones should just go back on the same way. No real tools necessary
if I remember correctly.

Providing I am understanding you correctly. I replaced the entire window
rubber on my '85 with the ones from my '90

Thanks,

Jeff
'85 GL (Gertie)
'78 Bus (Melissa) Patty's Bus