How do I reference variables from one editor script in another

I have one script that opens a simple editor window collects a bool and a string. I have another script derived from AssetPostprocessor that runs whenever assets are imported. I want to be able to toggle weather the importer script runs, and if so, where it gets materials from.

EditorWindow:

 public static bool Mat_to_Sub = false;
 public static string materialPath;

 void OnGUI()
 {
     GUILayout.Label ("Settings", EditorStyles.boldLabel);
     
     Mat_to_Sub = EditorGUILayout.BeginToggleGroup("Enable Material to Substance", Mat_to_Sub);
     
     if (GUILayout.Button("Location...")) 
     {
         materialPath = EditorUtility.OpenFolderPanel("Location of Materilas", "Assets/", "");
     }
     GUILayout.Label (materialPath);
     
     EditorGUILayout.EndToggleGroup();
 }

AssetPostprocessor script:

 public class ImportMattoSubstance :  AssetPostprocessor
 {        
     public Material OnAssignMaterialModel(Material material, Renderer renderer)
     {
         if (**bool from first script**) 
         {
             var materialPath = **string from first script** + material.name + ".sbsar";            
             
             if(AssetDatabase.LoadAssetAtPath(materialPath, typeof(Material)))
             {
                 return AssetDatabase.LoadAssetAtPath(materialPath, typeof(Material)) as Material;
             }
         }    
         
         return material;
     }
 }