JSFiddle - React, Tailwind, and code Playground

HTML

<form>
    <select>
        <option value="0">$0</option>
        <option value="50_Default" selected="selected">$50</option>
        <option value="100">$100</option>
        <option value="150">$150</option>
        <option value="200">$200</option>
    </select>
    <input type="submit" />
</form>

JavaScript

$('select').focus(function() {
    var option = $(this).find("option[value*=Default]");
    option.attr('value', option.attr('value').match(/[0-9]+/));
});

$('form').submit(function(e) {
    e.preventDefault();
    e.returnValue = false;
    
    alert($(this).find('select').val())
});