Here is a mini servo bracket for use with the standard Mg90 form factor 9g servos.

This can be mounted using 2 M2.5 countersunk screws under the servo or using a couple tabs also for M2.5 bolts on either side (which can be snipped off with wire cutter if not used).

The posts that hold the servo use M2 bolts where 8mm length is about right.

If your printer can do small resolution the screw holes work fine off the printer but if not you can always drill them out. If you want to use 4-40 screws you will need to drill them out just a little as they are just right for M2.5 screws for mounting.

Enjoy!