If you have bike shops around you that are owner operated then usually you can just go to them and they'll likely pull out their miscellaneous parts bin and find one. They might charge you a token sum or they might give it to you. Might depend on how likeable you are or whether the person you have to deal with is having a bad day.

I had to do that with my '91 Schwinn Paramount to find a stepped cable end for the compressionless cable housing for it's rear DR when I added a new 11 speed group to it a few years ago.