I destroyed my gasket doing the liner install. It seems to be just a ceramic fiber flat 6" gasket. The oem gasket goes for 44.00-60.00! Unreal for a stupid gasket. Now ive seen us stove sells them for a wopping 10.95. Has anyone used these interchangibly? Or does anyone know a good aftermarket supplier? My insert is a heatilator ecowins18/ quadrafire