A quick replacement if you mislay the camera mounting plate for your tripod. I've tried to use internal features for re-enforcement, adjust number of perimeters and layers so that the screw location has no infill and the retaining clip face is also solid. With $$$ of camera on top, this part needs to be rigid.
Print with support for the 90 degree overhang. I've uploaded a 2nd version of the model which has integrated support just in case this gives you better results (but will require some cleanup).
I also made a cap to cover the screw, this came out too tight a fit for me, but was easy to cleanup to get a push fit. If your screw has a loose D-ring, you might want this.
Print files for an Anet-A8, should be compatible with a Mk3.
The author hasn't provided the model origin yet.