This is a 3D printable version of a rip cord made to work with a vintage TOMY tron light cycle toy. It will probably work with various other toys from the 70's and 80's as well.
You can try printing it in flexible filament such as NinjaFlex or print a rigid version out and make a mold of it then cast it in Smooth-On's semi-rigid resin such as Smooth-Cast 65D or Simpact 85. Not sure what material would work best.
Unfortunately I was unable to get NinjaFlex to work with my printer. I ended up making a mold and casting one with Smooth-On's Smooth-Cast 65D. It works perfectly so my suggestion would be to mold and cast this after printing it.