If I open the ACIS (*.sat) file in Notepad it indicates that it was created in SolidWorks and saved as ACIS v22.
This indicates to me that the SolidWorks user is not very experienced (otherwise they would know to save as v7.
Opening either the ACIS or the STEP file in SolidWorks and running Import Diagnostics shows many errors.
Particularly one side of the thread faces missing.
This indicates to me that either the SolidWorks user is inexperienced or that they didn't want you to have a full model.
Given that they saved as ACIS v22 I am guessing inexperience.
In any case, this is a simple model. I would simply use the geometry they did supply only as reference to remodel the part from scratch in AutoCAD. Should take 15-20 minutes to model the part.
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