If you want that kind of functionality in the editor i think you will have to index the classname to the search index yourself.

Implementation would vary depending on search provider.

this should be what you're after

var contentTypeRepository= ServiceLocator.Current.GetInstance<IContentTypeRepository>();
var modelUsage = ServiceLocator.Current.GetInstance<IContentModelUsage>();

var blockType= contentTypeRepository.Load(typeof(BLOCKTYPE));

var items = modelUsage.ListContentOfContentType(blockType);

then use contentlink property on each of the items to get a reference to all the blocks/pages of that type.

I ment through the editor interface. Sorry if I was unclear.

I would yeild caution on contentModelUsage as I think this queries the database instead of cache.  My fellow collegues might know the answer about the database quering but I am pretty sure it does.

Sorry for the misunderstanding.

I am not sure you can without using episerver find or writing your own module to do so.  EPiServer find has "Power Slice" but you will need to have a find license.

you do something as follows

 [Component(PlugInAreas = "/episerver/cms/assets", Categories = "cms", WidgetType = "modeltypesearch/modelsearch", Title = "Content Type Search", Description = "")]
    [ServiceConfiguration(typeof(IContentQuery))]
  public class ModelTypeSearchComponent : ContentQueryBase
    {
  public override string Name
        {
            get { return "CustomQuery"; }
        }

        protected override IEnumerable<IContent> GetContent(ContentQueryParameters parameters)
        {
/ /Enter code above based on input to search for type.
}
}

<div>
    <div class="epi-gadgetInnerToolbar" data-dojo-attach-point="toolbar">
        <div data-dojo-type="dijit.form.TextBox" data-dojo-attach-point="queryText" data-dojo-props="intermediateChanges:true" data-dojo-attach-event="onChange: _reloadQuery"></div>
    </div>
    <div data-dojo-type="epi.cms.component.ContentQueryGrid" data-dojo-attach-point="contentQuery"></div>
</div>

The above is your template for the module.

then in module config, add the following

<?xml version="1.0" encoding="utf-8"?>
<module>
  <assemblies>
    <add assembly="YourAssemblyName" />
  </assemblies>
  <dojoModules>
    <add name="modeltypesearch" path="ModeTypelSearch" />
  </dojoModules>
</module>

Give that a try. 
so   the template and code goes in   
/modules/ModelSearch/templates
/modules/ModelSearch/modeltypesearchcomponents.cs