vracoop_pack_custo/views/templates.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>

    <template id="product_price" inherit_id="website_sale.product_price">
        <xpath expr="//h4" position="after">
            <t t-if="product.pack_ok">
                <h5><span t-esc="product.list_price_ref_pack" t-options="{'widget': 'monetary', 'display_currency': website.currency_id}"/><span> / kilo</span></h5>
            </t>
        </xpath>
    </template>

    <template id="products_item" inherit_id="website_sale.products_item">
        <xpath expr="//div[hasclass('product_price')]" position="replace">
	        <div itemprop="offers" itemscope="itemscope" itemtype="http://schema.org/Offer" class="product_price">
	            <b>
	                <t t-if="True"><!-- compatibility 12.0 -->
	                    <del t-attf-class="text-danger mr8 {{'' if combination_info['has_discounted_price'] else 'd-none'}}" style="white-space: nowrap;" t-esc="combination_info['list_price']" t-options="{'widget': 'monetary', 'display_currency': website.currency_id}" />
	                </t>
	                <t t-if="product.pack_ok">
	                	<span t-esc="product.price_ref_pack_compute" t-options="{'widget': 'monetary', 'display_currency': website.currency_id}"/>
	                </t>
	                <t t-else="">
		                <span t-if="combination_info['price']" t-esc="combination_info['price']" t-options="{'widget': 'monetary', 'display_currency': website.currency_id}"/>
		                <span itemprop="price" style="display:none;" t-esc="combination_info['price']" />
		                <span itemprop="priceCurrency" style="display:none;" t-esc="website.currency_id.name" />
		            </t>
	            </b>
	        </div>
	    </xpath>
    </template>

</odoo>