You can can save up to 20% off by purchasing a bundle through the Vuplex Store. To create a bundle, visit the cart page, click the checkbox next to each 3D WebView package you wish to purchase, and specify the number of licenses. The cart page automatically calculates a discount for the bundle and subtracts it from the total:
To purchase a bundle, it's necessary to use the Vuplex Store instead of the Unity Asset Store. For a description of the differences between the Vuplex Store and the Unity Asset Store, please see this page.