Hi - I have successfully recreated, 3D printed and tested, the little plastic wedge thingy/widget that acts as a ‘friction stop’ on the handlebar choke lever. Works like a charm and the choke lever stays exactly where you set it. For a spring, I used the spring from a cheapo pen and cut it to length to suit. If there’s interest, I can print some more for a donation plus postage. I’m in Malaysia but the part is tiny so shouldn’t be too expensive to post. Many thanks to TonyZXR for sending me some rough (very rough) drawings and measurements from the wooden one he made.