You could add to your module mymodule_preprocess_commerce_product()
hook function and inside that function get store entity and set twig variable with data from it so it will be available inside your template.
Check how original function looks like at:
/modules/contrib/commerce/modules/product/commerce_product.module
function template_preprocess_commerce_product(array &$variables) {
/** @var Drupal\commerce_product\Entity\ProductInterface $product */
$product = $variables['elements']['#commerce_product'];
$variables['product_entity'] = $product;
$variables['product_url'] = $product->isNew() ? '' : $product->toUrl();
$variables['product'] = [];
foreach (Element::children($variables['elements']) as $key) {
$variables['product'][$key] = $variables['elements'][$key];
}
}
So you'll have to fetch store object and assign twig variable like it's done here.