Well I figured out something that will work. I mainly needed to be able to put the cart button in the sidebar, so for the time being I’m using this:
<?php
$product = get_post_meta( post->ID, ‘product’, true);
echo print_wp_cart_button_new($product);
?>
Then I just put the full shortcode string with all variations into the ‘product’ meta field of my post. Quick and dirty, I don’t mind that.