Seat flip-forward lever

[ScottAndrews]

FWIW mine has these. I am going to retire these seats, so I may sell them as cores or part the trim out.

Side knobs don't look much different from your 3D printed ones...

 

[e9Leveque]

Scott - a bit hard to tell from your picture with the angle, but the ones we are having trouble finding are teardrop shaped like a gearshift. The “squashed teardrop” shape is more available. If you have the teardrop shape then someone would be happy to purchase them from you I suspect

 

[ScottAndrews]

They are indeed teardrop shaped, but they are not chrome AFAIK. A member already snagged them for postage