Persisting user preference for duration of session to filter product variation prices (WordPress, Woocommerce)

I would like the know the ideal way of adding a selection to the main nav of my wordpress/woocommerce site that lets users specify what region they prefer to see prices for. All the products have four variations, each one for a specific region and price. Someone from asia should then be able to select “asia” in a dropdown or radio button and only see product prices for asia when skimming through categories.

This setting should not be persisted to disk or db, only to session or something that works similarly in WP.

At the moment I have a filter set up for “woocommerce_variable_price_html” that simply replaces the “From X – Y$” format for prices with a hardcoded region price. But instead it should use the user specified region and then default to americas if none.

Thank you in advance! Let me know if anything needs elaboration.