JSFiddle - React, Tailwind, and code Playground

HTML

<div onclick='javascript:salelink("49.99", "50", "XS", "48")' class="button">ADD SALE COST</div>

<br /><br />

Exclusive sale offer: <span id="sale_item_price" class="bold price-new">&pound;100</span>

<br /><br />YOUR CHOSEN CHOICE<br /><br />
<select id="selectSize">
<option value="0"> --- Please Select --- </option>
<option value="999" name="Bespoke" id="Bespoke">Bespoke</option>
<option value="2">should not be chosen</option>
<option value="3">should not be chosen</option>
</select><br />

<input type="text" class="saleItemInformation"  id="saleItemInformation" value="" />



<input type="hidden" name="saleOtemPrice" value="0" id="saleOtemPrice">
<input type="hidden" name="custom_price" value="0" id="custom_price">
    

<script>
    function salelink(price_sale, psid, size, cid){
	
	$('#sale_item_price').html('&pound;'+price_sale+'');
	$('.saleItemInformation').attr('value', ''+psid+' Bespoke(Size:XS Colour:'+cid+') ');
	$('#selectSize option[id=Bespoke]').attr('selected', 'selected');
	$('#saleOtemPrice, #custom_price').val(''+price_sale+'');
	
	
}
    </script>

CSS

.button{cursor:pointer;border:1px solid #000;display:block;width:135px;padding:5px;text-align:center;text-transform:uppercase}