[s-cars] Gasket/Seal for Heater Box?

[Robert Rossato]

Anyone know the part number for the seal between the heater box and the
cowling?  Can't seem to find it in ETKA.  Anyone find a good equivalent?
Was thinking I might have to go to an HVAC supply place and see what they
may have but figured I'd check here first.  It appears to be around 10mm
thick by 20mm wide, medium density open cell foam with adhesive on both
sides.  Surely someone on here has done a heater core job, or three before.
I'd rather not reuse what's there as I don't trust it to seal again.

Thanks,
Bob