I only have 1 left, make offer. The foam is there but the rubber overcoat should probably be re-covered or re-coated to make them last a bit longer considering replacements are not available anywhere. You could dunk it in that liquid "Plasti-Dip" stuff prior to install or use the high-end 3M rubber glue to cover it with a piece of tire sidewall or something like that. Part number GM 15989675 (Discontinued).
In the last picture you can see the significantly larger ZQ8, Xtreme, SS bump stop next to the base model bump stop. A ZQ8, Xtreme, SS, or lowered truck practically sits on these larger bump stops