mirrors on 1990 454 SS truck??????

[waynep]

i have a 1990 454 SS truck. i am wanting to replace the rubber gasket between the SPORT Mirror and door. i have not been able to locate these. i have the original metal mirrors on the truck and the new replacement mirrors look to be plastic with a foam gasket. the part number on the rubber gasket is 75646327 LH AND 15646328 RH. I am finding that some sites says this the entire mirror assembly which is discontinued and another site says this is just the gasket which is also discontinued. Does anyone make a replacement gasket for the sport mirrors????