Are you looking for the bulb rubber seal that fits on the edge of the sheet metal? If so, check Amazon out. Just make sure you get the right thickness. I ordered mine from amazon...
Trim-Lok Trim Seal with Side Bulb - PVC Plastic Trim with EPDM Rubber Bulb Seal - Fits 1/8" Edge, 3/4" Bulb Seal Diameter, 25' Length
https://www.amazon.com/dp/B00NL46NOY..._x14XDbBS1YWT5