Update: I have some knobs made! Two members here had messaged me saying they need seat knobs and I finally got around to doing some 3-d printing. I have two finishing methods, one with plastidip and the other with acetone. The outcome is a bit different, so I’m going to send both types to the two people who had already messaged me and have them decide which is better. At that point I’m happy to print off a bunch more as people need them. I think that final price will be about $20 including shipping within the US, can figure out international as needed. That’s about $7-8 for the shipping and the rest for my daughter who has been helping to make them.