I know that product, though never used it. My Dad used that stuff on all kinds of stuff - he kept multiple colors in his work desk!
I have been having problems finding what might work and finding it in white has been near impossible - when searching "o-rings". Just yesterday I was pondering what else I could look for and my mind finally drifted on another hobby I have - Pinball Machines (specifically electromagnetic pinballs). I might be able to find a suitable size for one of the smaller "rubber bands" for posts. I have various sizes back in Texas and I am eager to see if I have something in "stock" that could work when I get home to Texas later this week.
Edit:
Also, the material that is left on one of my Engines actually reminds me how old Pinball rubber bands discolor & degrade over a long period of time.