changing variant.id on change via span

[Chris_Sydney]

Hey, 

Wondering if anyone knows if its possible to change a variant.id on change of the variant like the variant.sku?

like this effectively but for variant.id (and ideally variant.compare-to-price and variant.price)

{% assign current_variant = product.selected_or_first_available_variant %}
<span class="variant-sku">{{ current_variant.sku }}
</span>

could write the JS for this, but figured it probably exists somewhere as a class so wanted to save myself the headache.