Made this after I printed a bunch of the JessEm inserts by SkippyMcSlappyPants.
I used some of the 1/4 oz wheel weights from Hazard Fraught and some 3.5in 16D nails that I rounded the tops on. The voids in the bottom of the part are sized for these.
Print normally with supports to avoid sagging, I used PETG CF printed at a 0.6mm layer height.

Will upload more pics later if I get a chance.

https://www.harborfreight.com/1-4-quarter-oz-wheel-weights-67225.html