top of door rubber ring missing

Thanks for writing in. While I can't be certain what you have without seeing the original hardware, I unfortunately am almost we certain we cannot replace the individual rubber guides you're referring to. However, if the guides look like those atop our 23-222C, you might be able to use this to replace your old roller outright. If in doubt however, send us photos of your old roller removed from the closet and we'd be happy to confirm if this is the right choice for you.