Jquery – How to pass attributes to select2

I'm using Select2 4.0. I have a list of options, some of which are "deleted" and I want to signify which are which. My select element is like this:

<style>.deleted { color: red; }</style>

<select name="itemid" id="item-list" tabindex="1">
    <option></option>
    <option value="1">Item 1</option>
    <option value="2" class="deleted">Item 2</option>
    <option value="3">Item 3</option>
</select>

And it's initialised like this:

<script src="/static/js/select2.min.js"></script>
<script>
$(function() {
    $("#item-list").select2({
        placeholder: 'Select item'
    });
});
</script>

However, on the resulting HTML code that select2 generates I don't see any way to reference that class. Also tried a data-deleted attribute on the option, with no luck.

The only thing I see that comes close is the templateResult option, where I can check for opt.element.className. But I cannot see how to access the select2 option from there. Anyway that callback runs on every single search which is not at all what I want.

Is there some other way to style particular options in Select2?

UPDATE: as noted in the comments there is a find() function, but that only gets the original <option> elements, not the <li> elements that select2 generates. Here's what I tried:

var sel2 = $("#item-list").select2({
    placeholder: 'Select item'
});

sel2.find('.deleted').each(function() {
    $(this).css('color', 'red');
});