Does anyone know the exact dimensions of the injector return line O ring seals. I have a 98 E300D, and also the material they are made of?

I believe that the part nos are: 601 997 04 45, and 601 997 03 45.

I know I can get them mail order but I would like to expedite this task and its been my experience that O rings are common sizes similar to bearings. Perhaps the difference being the material they are made of.

I would like to source them locally if I can, and not wait for the mail order, plus I need exact dimensions because I only have the one vehicle and it would be difficult for me to shop for replacements since I live in a remote area.

Any help would be greatly appreciated.