Another 69 RR Master Brake Cylinder Question

I’ve puller the Master Brake Cylinder, and noticed that the black little rubber washer around the rod that goes into the master cylinder which comes off the brake foot pedal looks worn. My question is, I would like to replace it, and can I buy the washer separately or do I need to replace the whole rod? Take a look at the attached photo I circled the rubber washer with white.

Also, where is a good online place to buy the master cylinder............
Thanks

Frank from Delaware

The small blk. washer that’s on the end of the rod is to hold the rod in place and to prevent it from falling out. When you purchase a new (rebuilt) master cylinder it should come with it, make sure you check.