Rod Holder/Rocket Launcher "Plastic" Liners?

Hey guys - our 1991 41C has Stainless Steel "rocket launchers" or rod holders across the rear of the cabin and also across the rear of the flybridge.

Each rod holder has a plastic insert that is 2" (inside diameter of the stainless tube) - see photos...

Does anyone have ideas/options of places to buy these replacement plastic (or PVC) inserts? I figure many of us have the same issue

(I searched the newsgroups and could not find another post about this).

Thank you. Steve

Years ago, West Marine had something close enough for us.
Model # 18954636
One small lil rivet held ours in.

Would you know your mfg?

Google vinyl rod holder liner replacement

Thank you!!!