In order to make a uploadable product, first make a new product with associated pricing and configurations under Catalogue -> Products -> Manage Products and then navigate to Catfish -> Infigo Variable Data -> Multipart Product.
Find the product from the dropdown and make sure "Create a user upload product" is checked.
In order to charge per page, Edit the newly created product and adjust the value of "PricePerPage"
The final step is to enabled Multi Part products to be visible on Shared Print Operations. To do this, navigate to Catfish > Infigo Variable Data > Infigo Settings > : True > Save