Experimental code (not yet working) to make items in the media library non-selectable.

disable-media.js

//wp.media.view.Modal.prototype: open, ready
( function ($) {
	var $attachments = $('.attachments').children(),
		blocked = [ 1, 2, 12, 4593 ];

	wp.media.events.on( 'open', function( arguments ) {
		alert('event fired')
	});

	$attachments.each( function(index) {
		var $this = $(this),
			id = $this.data("id");
		if ( -1 !== blocked.indexOf( id ) ) {
			$this.children( '.js--select-attachment' ).removeClass( 'js--select-attachment' );
		}
	});