JSFiddle - React, Tailwind, and code Playground

HTML

<script type="text/javascript" src="http://code.jquery.com/jquery-latest.js"></script>

<form method="post" class="product js-recalculate" action="/antilopa/kartiny">
					<div class="product-fields">
								<div class="product-field product-field-type-S">
					<span class="product-fields-title-wrapper">
                        <span class="product-fields-title"><strong>Тип багета</strong></span>
					</span>

				<span class="product-field-display">
				   						  <select name="customPrice[0][10]" required="" class="baget_select">
                                              
							 <option disabled="">Выберите багет</option>
							 <option value="5788">темный</option><option value="5789">светлый</option>						  </select>
									</span>
					<span class="product-field-desc"></span>
				</div>
    </div>
			
		<div class="addtocart-bar">
		<span class="quantity-box">
		<input type="text" class="quantity-input js-recalculate" name="quantity" value="1">
	    </span>
		<span class="quantity-controls js-recalculate">
			<input type="button" class="quantity-controls quantity-plus">
			<input type="button" class="quantity-controls quantity-minus">
	    </span>
				
		<span class="addtocart-button with_baget">
			<input type="submit" name="addtocart" class="addtocart-button" value="Добавить в корзину" title="Добавить в корзину" disabled>		
        </span>
            
        <span class="addtocart-button with_baget">
			<input type="submit" name="addtocart" class="addtocart-button" value="Добавить в корзину" title="Добавить в корзину" disabled>		
        </span>
				
			<div class="clear"></div>
		</div>
				<input type="hidden" class="pname" value="Картина-панно &quot;Скрипачка, контрабасист, саксофонист&quot; на натуральном камне оникс">
		<input type="hidden" name="option" value="com_virtuemart">
		<input type="hidden" name="view" value="cart">
		<noscript>&lt;input type="hidden" name="task" value="add"/&gt;</noscript>
		<input type="hidden"...

JavaScript

jQuery(function($) {
	function imageBagetSelect(){
		if( String(window.location).indexOf("-detail") > 0 ){
			if( $('.bagetImg').length ) {
			   $('.bagetImg').remove();
			}
			if($(".baget_select option:selected").text()=="темный"){
			   $( '.addtocart-area .product-field-type-S').after( '<img class="bagetImg" src="/images/banners/dark_baget.jpg" alt="Тёмный багет" title="Тёмный багет" />' );
			} else if ($(".baget_select option:selected").text()=="светлый"){
			   $( '.addtocart-area .product-field-type-S').after( '<img class="bagetImg" src="/images/banners/light_baget.jpg" alt="Светлый багет" title="Светлый багет" />' );
			}
		}
		var elements = $('span.addtocart-button');
		var button = 0;
		for(var i=0; i<elements.length; i++) {
			var selection = $(elements[i]).parent().prev().find('.baget_select option:selected');
			if (selection.length > 0 ){
				button = $(elements[i]).find('input.addtocart-button');
				if(selection.text()=='Выберите багет'){
					$(button).prop("disabled", true);
				} else {
					$(button).prop("disabled", false);
				}
			}
		}
	}
	
	imageBagetSelect();
	$('.baget_select').on('change', function(){
        imageBagetSelect();
	});
	
	$('span.addtocart-button').on('click', function(){
		if($(this).parent().prev().find('.baget_select').length > 0){
			if($(".baget_select option:selected").text()=='Выберите багет'){
				alert('Выберите тип багета!');
			}
		} 
	});
	
});