Ever since I first saw Return to Oz as a child, I've wanted my own Oz key like the one Dorothy had in the film. Now, thanks to a little bit of 3D modeling skill, a paused DVD, and some other reference material, I've realized that dream without buying some badly-molded nth-generation prop copy off evilBay.
I made this while eyeballing screenshots from the film as well as the photos of actual surviving prop keys on this Return to Oz site.
This key is for sale on Shapeways; if you'd like to get it printed on industrial gear, in metal or other materials, buying it from my shop would be very cool of you: https://www.shapeways.com/product/7TWY4KCSF/return-to-oz-key . The polished bronze steel is my favorite material for this, an example print is shown here.
Print/paint/patina/plate/mold/whatever in your choice of finish, from the rusty dirty key Dorothy first finds in Kansas to the gleaming gold version Bellina wears in the Emerald City parade.
I recommend gently polishing or sanding down the sharp corners for that rounded used-key look. If you're printing in ABS you might try very light use of a heat gun for this, be very careful.
If you're printing in plastic, using 100% infill will result in a durable key that hangs and feels a bit more like a metal key would for jewelry and costume purposes.
The metal key shown was printed at Shapeways in Polished Bronze Steel. The painted plastic key shown in an attached photo was printed at 200 micron layer height in black PLA on a Replicator 2, and painted with oil-based paint pens as a quick test. The silver key shown in the last photo was printed in metallic silver ABS at 100 micron layer height.