The fund can be changed on a per product basis:
  1. While logged into NetCommunity, navigate to the Estore Administration page
  2. Navigate to the Inventory tab
  3. Click Edit next to the product in question
  4. Scroll to the Fund section and click Change
  5. Locate your desired fund and click Select
  6. Click Save Inventory Item at the bottom of the page
Repeat for any other products.

For more information on eStore.