[Silverthorn]

I need to replace a hop-up nub (or is it named bucking? it's the little rubber thing that pushes on the hop-up rubber).

EDIT : needed replacement solutions for both AEG and VSR-10. Thanks for concave spacers suggestion. Knew about them but never thought to look at airsoftparts.ca to purchase them. What about for VSR-10 now?

I know you can use the pipe-like end of a Bic pen because it's the same size but it's also much much more rigid. I would like to test out different hardness.

Where can you buy the piping used to make nubs (so I could cut them myself)?

Or where can you buy nubs by themselves? All I have seen on online stores are full sets that include the nub.

Or whate else can be used as a replacement instead of a Bic pen pipe?

Thanks.