JSFiddle - React, Tailwind, and code Playground

HTML

<select>
    <option>abc - abchsdklksd</option>
        <option>abcdfe - akdskdfsaljdfsklfdjf</option>
            <option>sag - sdalkjdfjfl</option>
</select>

JavaScript

var max_len = 0;
$("select option").each(function(){
    var cur = $(this);
    var cur_len = cur.html().indexOf("-");
    if(cur_len > max_len){
        max_len = cur_len;
    }
});
$("select option").each(function(){
    var cur = $(this);   
    var no_of_spaces = max_len - cur.html().indexOf("-");
    var nbsps = "";
    for(var i=0;i<no_of_spaces;i++){
        nbsps = nbsps + "&nbsp;";
    }
    cur.html(cur.html().replace("-",nbsps + " -"));
});