The bumpers on my Star Wars had also melted to black goo leaving just the metal inserts on the mounting screws. Here is what I did:
I went to Ace and to the plumbing department. There you will find a parts bin full of sink washers/gaskets. I found 4 slightly cone shaped washers that were about the right diameter for the metal inserts I had. I cleaned the old metal inserts, coated them with shoo goo (silicone glue), and pressed the washers on so they were even with the bottom of the metal insert. After they dried, I trimmed the top of the washer off even with the top of the metal insert with a razor knife. Re-installed and they have not failed me yet.
Oh yeah... they were 65 cents each. I got a pack of 8 acceptable trigger springs from Lowe's from the screen door/window repair aisle for about $2-$3....