Hello, @chrishayes,
With the theme purchase, you always get 6 months of free support with each purchase, you can purchase the theme from here: https://themeforest.net/item/porto-responsive-wordpress-ecommerce-theme/9207399
Have you already purchased the theme? and your support is expired and you want to renew the support, then please refer to Envato articles here: https://help.market.envato.com/hc/en-us/articles/208191263-What-is-Item-Support & https://help.market.envato.com/hc/en-us/articles/207886473-Extend-or-renew-Item-Support
We hope this helps.
Best Regards,
PThemes Team.