Walk around the old hardware store and find a plastic angled piece that is used for a totally different purpose (for example a door jam or a door molding piece) and see if you can make it work.
I always find other uses for stuff they sell.
I have a cement edge in the garage that is below the wall and at the right height for my wife to smack her door when she gets out. I wanted to put a piece of rubber there, but could not find anything.
Ended up buying a plastic/rubber transition piece for carpeting. Works great.
