Been having some issues with the printer. Spare parts ordered ! I have seen these and was thinking about trying one. There are however issues with these. Once you have used it you need to wipe it, easier to wipe you fingers ? It solves one problem to create another . There was one I saw that has a sheath to print to put it in. I’ll get my printer fixed and see .
Clever re-purposing ... though won't sit flat in one's pocket.
Kickstarter or something has brass door openers, purposely made of brass for its microbial properties. I would also note that 3-D printed may not be smooth, and may have tiny spots for the virus to reside, so please ensure you clean them properly. Stay safe!