Actually, you know what? Here’s how to make a super safety.

You need to wiggle the geometry in cad a little bit to be able to use 1/8” end mills. I think there are already some models floating around with the changes, but basically the slot for the lever needs to be widened a bit, and the pocket needs to be changed to radiuses that can fit the 1/8” tool. The bulge on the end of the lever needs to be thickened to match. Add a 1/2” or 12mm square boss on the non slot end so you can hold it in a vise. Orient the square boss so that if you lay the whole thing on its side, the safety detent grooves and trigger interfaces have no overhangs. Maybe I’ll just post it.

Use a 12mm square stock of preferably 17-4ph as you can heat treat it. Stand it upright in the vise. Mill out the diameter of the of the safety with a rigid tool, like 6mm or 1/4” end mill. Your tool stick out should be a little more than the length of the SS for clearance.

With the same orientation in the vise, use a 1/8” bull nose end mill (bull nose is less likely to chip a tooth) to mill out the lever pocket.

Flip it on its side in the vise so that where you want the detent and trigger interface geometry is straight up. Use a 1/16” ball nose endmill with 3D adaptive clearing to mill those pockets.

Saw cut off the square on the end and boom, you have yourself a homemade SS in heat treatable steel. If you want to heat treat it, use the H900 process, it’s stupid simple if you have a kiln or oven with the right temps.