the zip file includes the sixteen allomantic metals, they are sized for earrings here but you can scale them bigger for keychains or make them smaller for for more delicate pieces.

the regular scale ones require a brim or they will warp. bigger pieces won't need it.

if you have SLA printers you might be able to get smaller pieces.

0.1 layer height
20% infill 
infill pattern grid
3 bottom layers
4 top layers