Awesome! Thanks! I think I can use the end of a snap ring as a spacer.
If I were going to make one (which is a great idea by the way) :
I'd find a metal tube that has an inner diameter that works for you. That is the hardest part to create.
You don't really care about the outside because you can fix that.
Take the tube and toss it in a drill. Take sandpaper and bring the outer diameter down to what it needs to be.
Then cut to your desired length.