Lego Technic 32439a

This is my second attempt to upload a piece on here- so do forgive me if i get this wrong.
This is Lego Technic piece 32439a (A Disk Brake) Not found on any website that I know of..(and there are quite a few) The piece was found on LeoCAD and converted into a STL file using MeshLab- however the object was changed in size- I tried to correct this.
I do have the actual piece and broadly made an assumption on the scale using an electronic digital caliper- the Cura version I was using to resize it made it massive!